manpagez: man pages & more
man remind(1)
Home | html | info | man
remind(1)                                                            remind(1)




NAME

       remind - a sophisticated reminder service


SYNOPSIS

       remind [options] filename [date] [*rep] [time]


DESCRIPTION

       Remind  reads  the supplied filename and executes the commands found in
       it.  The commands  are  used  to  issue  reminders  and  alarms.   Each
       reminder  or alarm can consist of a message sent to standard output, or
       a program to be executed.

       If filename is specified as a single dash '-', then  Remind  takes  its
       input from standard input.  This also implicitly enables the -o option,
       described below.

       If filename happens to be a directory rather than a  plain  file,  then
       Remind  reads all of the files in that directory that match the pattern
       "*.rem".  The files are read in sorted order; the sort order may depend
       on  your  locale,  but should match the sort order used by the shell to
       expand "*.rem".

       Remind reads its files starting from the beginning to the end, or until
       it  encounters  a  line  whose  sole  content is "__EOF__" (without the
       quotes.)  Anything after the __EOF__ marker is completely ignored.



OPTIONS

       Remind has a slew of options.  If you're new  to  the  program,  ignore
       them for now and skip to the section "REMINDER FILES".

       -n     The -n option causes Remind to print the next occurrence of each
              reminder in a simple calendar format.  You can sort this by date
              by  piping  the output through sort(1).  Note that the -n option
              causes any -g option to be ignored.

       -j[n]  Runs Remind in "purge" mode to get  rid  of  expired  reminders.
              See the section PURGE MODE for details.

       -r     The  -r option disables RUN directives and the shell() function.

       -c[flags]n
              The -c option causes Remind to produce a calendar that  is  sent
              to  standard  output.  If you supply a number n, then a calendar
              will be generated for n months, starting with the current month.
              By default, a calendar for only the current month is produced.

              You  can  precede n (if any) with a set of flags.  The flags are
              as follows:

              '+'    causes a calendar for n weeks to be produced.

              'a'    causes Remind to display reminders on the calendar on the
                     day  they actually occur as well as on any preceding days
                     specified by the reminder's delta.

              'l'    causes Remind to use  VT100  line-drawing  characters  to
                     draw  the  calendar.   The  characters are hard-coded and
                     will only work on terminals that emulate the  VT00  line-
                     drawing character set.

              'u'    is similar to 'l', but causes Remind to use UNICODE line-
                     drawing characters to draw the calendar.  The  characters
                     are  hard-coded  and will only work on terminals that are
                     set to UTF-8 character encoding.  This flag also  enables
                     the  use of the UNICODE "left-to-right" mark that can fix
                     up formatting problems with  right-to-left  languages  in
                     the calendar display.

              'c'    causes  Remind  to use VT100 escape sequences to approxi-
                     mate SPECIAL COLOR reminders.  Note  that  this  flag  is
                     kept  for  backwards-compatibility;  you  should  use the
                     -@[n][,m] command-line option instead.


       -@[n][,m]
              Tells Remind to approximate SPECIAL COLOR reminders using  VT100
              escape  sequences.   The  approximation  is  (of necessity) very
              coarse,  because  the  VT100  only  has  eight  different  color
              sequences, each with one of two brightnesses.  A color component
              greater than 64 is considered "on", and  if  any  of  the  three
              color  components  is  greater than 128, the color is considered
              "bright".

              If you supply the optional numeric parameters, the have the fol-
              lowing  meanings:  n=0 tells Remind to use the standard 16 VT100
              colors.  n=1 tells it to use an extended 256-color palette  sup-
              ported  by many terminal emulators such as xterm.  And n=2 tells
              it to use escape sequences  that  support  true  24-bit  colors,
              again supported by many terminal emulators such as xterm.

              If  the optional m parameter is supplied following a comma, then
              m=0 tells Remind that  the  terminal  background  is  dark,  and
              Remind  will  brighten  up dark colors to make them visible.  If
              m=1, then Remind assumes the terminal background is light and it
              will darken bright colors to make them visible.  If no m is sup-
              plied, then Remind does not perform any  adjustments,  and  some
              reminders  may  be hard or impossible to see if the color is too
              close to the terminal background color.

       -wcol[,pad[,spc]]]
              The -w option specifies the output width, padding and spacing of
              the formatted calendar output.  Col specifies the number of col-
              umns in the output device.  If not specified, or specified as 0,
              it defaults to the larger of 71 or the actual width of your ter-
              minal, or to 80 if standard output is not a terminal.

              Pad specifies how many lines to  use  to  "pad"  empty  calendar
              boxes.   This defaults to 5.  If you have many reminders on cer-
              tain days that make your calendar too large to fit  on  a  page,
              you  can  try reducing pad to make the empty boxes smaller.  Spc
              specifies how many blank lines to leave between the  day  number
              and the first reminder entry.  It defaults to 1.

              Any of col, pad or spc can be omitted, providing you provide the
              correct number of commas.  Don't use any spaces in the option.

       -s[a]n The -s option is very similar to the -c option, except that  the
              output  calendar  is  not  formatted.  It is listed in a "simple
              format" that can be used as input for more sophisticated  calen-
              dar-drawing  programs.   If n starts with "+", then it is inter-
              preted as a number of weeks.

              If you immediately follow the s with the letter a,  then  Remind
              displays  reminders  on  the  calendar  on the day they actually
              occur as  well  as  on  any  preceding  days  specified  by  the
              reminder's delta.

       -p[a][p][p]n
              The  -p option is very similar to the -s option, except that the
              output contains additional information for  use  by  the  Rem2PS
              program,  which creates a PostScript calendar, and various other
              back-end programs.  For this option, n cannot start with "+"; it
              must specify a number of months.  The format of the -p output is
              described in the rem2ps(1) man page.  If you immediately  follow
              the  p  with the letter a, then Remind displays reminders on the
              calendar on the day they actually occur as well as on  any  pre-
              ceding  days  specified  by the reminder's delta.  If you follow
              the p with another p, then  Remind  uses  a  more  comprehensive
              JSON-based  format  rather  than  the  "simple calendar" format.
              This format is  also  documented  in  the  rem2ps(1)  man  page.
              Finally,  if  you  use three p's, as in -ppp, then Remind uses a
              pure JSON format, again documented in rem2ps(1).

              Note that the -pp or -ppp options also enable the -l option.

       -l     If you use the -l option in conjunction with the -p option, then
              Remind outputs additional information for back-end programs such
              as rem2ps.  This additional information lets the  back-end  pro-
              grams  correlate a reminder with the source file and line number
              that produced it.

       -m     The -m option causes the -c or -p options to produce a  calendar
              whose first column is Monday rather than Sunday.  (This conforms
              to the international standard.)

       -v     The -v option makes the output of Remind slightly more  verbose.
              Currently,  this  causes Remind to echo a bad line in case of an
              error, and to print a security message if  a  script  tests  the
              $RunOff system variable.

       -o     The -o option causes Remind to ignore all ONCE directives.

       -t     The   -t   option  causes  Remind  to  trigger  all  non-expired
              reminders, regardless of the delta supplied for each reminder.

       -tn    If you supply a number n after the -t option, then  Remind  pre-
              tends  that  each non-expired reminder has a delta of n days and
              triggers reminders accordingly.

       -tt[n] The -tt option causes Remind to assume a default delta of n min-
              utes  for  all  timed  reminders.   If -tt is given with no n, a
              default delta of 5 minutes is used.

       -h     The -h option ("hush...") suppresses certain warning and  infor-
              mation  messages.  In particular, if no reminders are triggered,
              this mode produces no output.

       -a     The -a option causes Remind not  to  immediately  trigger  timed
              reminders  that  trigger  on  the  current  day.  It also causes
              Remind not to place timed reminders in a calendar.  If you  sup-
              ply  two  or  more  -a  options,  then Remind will trigger timed
              reminders that are in the future, but  will  not  trigger  timed
              reminders  whose  time  has  passed.  (Regardless of how many -a
              options you supply, Remind will not include timed  reminders  in
              the calendar if at least one -a option is used.)


       -q     The  -q  option  causes  Remind not to queue timed reminders for
              later execution.

       -f     The -f option causes Remind to remain  in  the  foreground  when
              processing  queued  reminders,  rather  than forking off a back-
              ground process to handle them.

       -e     The -e option diverts error messages (normally sent to the stan-
              dard error stream) to the standard output stream.

       -dchars
              The  -d option enables certain debugging modes.  The chars spec-
              ify which modes to enable:

         e      Echo all input lines

         x      Trace all expression evaluation

         t      Display all trigger date computation

         v      Dump the variable table after execution of the reminder script

         l      Echo lines when displaying error messages

         f      Trace the reading of reminder files

       -g[a|d[a|d[a|d[a|d]]]]
              Normally,  reminders  are  issued in the order in which they are
              encountered in the reminder script.  The -g option cause  Remind
              to  sort  reminders by date and time prior to issuing them.  The
              optional a and d characters specify the sort order (ascending or
              descending)  for  the  date,  time and priority fields.  See the
              section "SORTING REMINDERS" for more information.

              Note that -g is ignored if you use the -n option.

       -b[n]  Set the time format for the calendar  and  simple-calendar  out-
              puts.   N can range from 0 to 2, with the default 0.  A value of
              0 causes times to be inserted  in  12-hour  (am/pm)  format.   1
              causes  times  to  be inserted in 24-hour format, and 2 inhibits
              the automatic insertion of times in the calendar output.

       -x[n]  Sets the iteration limit for the SATISFY clause of  a  REM  com-
              mand.  Defaults to 1000.

       -kcmd  Instead  of simply printing MSG-type reminders, this causes them
              to be passed to the specific cmd.  You must use '%s'  where  you
              want  the body to appear, and may need to enclose this option in
              quotes.  Note that all shell  characters  in  the  body  of  the
              reminder  are  escaped  with a backslash, and the entire body of
              the reminder is passed as a single  argument.   Note  that  this
              option overrides the -r option and the RUN OFF command.

              As an example, suppose you have an X Window program called xmes-
              sage that pops up a window and  displays  its  invocation  argu-
              ments.  You could use:

                        remind '-kxmessage %s &' ...

              to have all of your MSG-type reminders processed using xmessage.

              A word of warning: It is very easy to spawn dozens  of  xmessage
              processes  with  the  above  technique.   So  be  very  careful.
              Because all shell and whitespace  characters  are  escaped,  the
              program  you execute with the -k option must be prepared to han-
              dle the entire message as a single argument.

       -z[n] Runs Remind in the daemon mode.  If n
              is supplied, it specifies how often (in minutes)  Remind  should
              wake  up  to  check  if the reminder script has been changed.  N
              defaults to 1, and can range from 1 to 60.  Note that the use of
              the -z option also enables the -f option.

              If  you  supply  the  option  -z0, Remind runs in a special mode
              called server mode.  This is  documented  in  the  tkremind  man
              page; see remind(1).

       -uname Runs  Remind with the uid and gid of the user specified by name.
              The option changes the uid and gid as described,  and  sets  the
              environment  variables  HOME,  SHELL and USER to the home direc-
              tory, shell, and user name, respectively, of the specified user.
              LOGNAME  is also set to the specified user name.  This option is
              meant for use in shell scripts that mail reminders to all users.
              Note  that  as of Remind 3.00.17, using -u implies -r -- the RUN
              directive and shell() functions are disabled.  However,  if  you
              prefix  name  with  a  +-sign, then RUN and shell() are not dis-
              abled.  That is, -uwhatever switches the user  to  whatever  and
              disables  RUN, whereas -u+whatever switches the user to whatever
              but leaves RUN enabled.

              Non-root users can also use the -u  option.   However,  in  this
              case,  it  only  changes  the environment variables as described
              above.  It does not change the effective uid or gid.

       -+username
              Causes Remind to trust files owned by the user  username.   Nor-
              mally,  if  Remind reads a file that you do not own, it disables
              RUN and the shell() function.  This option  causes  it  to  also
              trust  files  owned  by  username.   You  can supply multiple -+
              options to trust multiple users, up to a  limit  of  20  trusted
              users.

       -y     Causes  Remind to synthesize a tag for any reminder that lacks a
              TAG clause.

       -ivar=expr
              Sets the value of the specified var to expr, and preserves  var.
              Expr  can be any valid Remind expression.  See the section "INI-
              TIALIZING VARIABLES ON THE COMMAND LINE" for more details.

       -ifunc(args)=definition
              Allows you to define a function on the command line.

       If you supply a date on the command line, it must consist of day  month
       year,  where  day  is the day of the month, month is at least the first
       three letters of the English name of the month, and year is a year (all
       4  digits)  from  1990 to about 2075.  You can leave out the day, which
       then defaults to 1.

       If you do supply a date on the  command  line,  then  Remind  uses  it,
       rather  than  the  actual  system date, as its notion of "today."  This
       lets you create calendars for future months, or test to  see  how  your
       reminders will be triggered in the future.  Similarly, you can supply a
       time to set Remind's notion of "now" to a particular time.  Supplying a
       time on the command line also implicitly enables the -q option and dis-
       ables the -z option.  The time may be specified in 24-hour format  (eg,
       13:20) or common "AM/PM" format (1:20pm).

       If you would rather specify the date more succinctly, you can supply it
       as YYYY-MM-DD or YYYY/MM/DD.  You can even supply a date  and  time  on
       the command line as one argument: YYYY-MM-DD@HH:MM.

       In  addition,  you  can  supply  a repeat parameter, which has the form
       *rep.  This causes Remind to be run rep times, with the date increment-
       ing on each iteration.  You may have to enclose the parameter in quotes
       to avoid shell expansion.  See the subsection "Repeated  Execution"  in
       the section "CALENDAR MODE" for more information.


REMINDER FILES

       Remind  uses  scripts  to  control its operation.  You can use any text
       editor capable of creating plain ASCII files to create a Remind script.
       The  commands inside a script can range from the very simple and almost
       immediately understandable:

            REM 6 Jan MSG Dianne's birthday

       to the baroque and obscure:

            REM [date(thisyear, 1, 1) + 180] ++5 OMIT \
            sat sun BEFORE MSG [ord(thisyear-1980)] payment due %b!

       A reminder file consists of commands, with one command per line.   Sev-
       eral  lines  can  be continued using the backslash character, as in the
       above example.  In this case, all of the concatenated lines are treated
       as  a  single  line  by  Remind.   Note that if an error occurs, Remind
       reports the line number of the last line of a continued line.

       Remind ignores blank lines, and lines beginning with  the  '#'  or  ';'
       characters.   You  can  use the semicolon as a comment character if you
       wish to pass a Remind script through the C pre-processor, which  inter-
       prets the '#' character as the start of a pre-processing directive.

       Note  that  Remind  processes  line continuations before anything else.
       For example:

            # This is a comment \
            This line is part of the comment because of line continuation \
            and so on.
            REM MSG This line is not ignored (no \ above)

       Remind is not case sensitive; you can  generally  use  any  mixture  of
       upper- or lower-case for commands, parameters, invocation options, etc.


THE REM COMMAND

       The most powerful command in a Remind script is the REM command.   This
       command is responsible for issuing reminders.  Its syntax is:

              REM  [ONCE]  [date_spec] [back] [delta] [repeat] [PRIORITY prio]
              [SKIP | BEFORE | AFTER]  [OMIT  omit_list]  [ADDOMIT]  [OMITFUNC
              omit_function]  [AT  time [tdelta] [trepeat]] [SCHED sched_func-
              tion]  [WARN  warn_function]  [UNTIL   expiry_date   |   THROUGH
              last_date]  [SCANFROM  scan_date  |  FROM  start_date] [DURATION
              duration] [TAG tag] <MSG | MSF | RUN | CAL | SATISFY  |  SPECIAL
              special | PS | PSFILE> body

       The parts of the REM command can be specified in any order, except that
       the body must come immediately after the MSG, RUN, CAL, PS,  PSFILE  or
       SATISFY keyword.

       The  REM token is optional, providing that the remainder of the command
       cannot be mistaken for another Remind command such as OMIT or RUN.  The
       portion  of  the  REM  command  before the MSG, MSF RUN, CAL or SATISFY
       clause is called a trigger.

       MSG, MSF, RUN, CAL, SPECIAL, PS and PSFILE

       These keywords denote the type of the reminder.  (SATISFY is more  com-
       plicated  and  will  be explained later.)  A MSG-type reminder normally
       prints a message to the standard output, after passing the body through
       a  special substitution filter, described in the section "THE SUBSTITU-
       TION FILTER."  However, if you have used the  -k  command-line  option,
       then  MSG-type  reminders  are passed to the appropriate program.  Note
       that the options -c, -s, -p and -n disable the -k option.

       Note that you can omit the reminder type, in which case it defaults  to
       MSG.  So you can write:

            6 January Dianne's Birthday

       although this is not recommended.

       The  MSF keyword is almost the same as the MSG keyword, except that the
       reminder is formatted to fit into a paragraph-like format.  Three  sys-
       tem  variables  control the formatting of MSF-type reminders - they are
       $FirstIndent, $SubsIndent and $FormWidth.  They are  discussed  in  the
       section "SYSTEM VARIABLES."  The MSF keyword causes the spacing of your
       reminder to be altered - extra spaces are discarded, and two spaces are
       placed  after  periods and other characters, as specified by the system
       variables $EndSent and $EndSentIg.   Note  that  if  the  body  of  the
       reminder   includes  newline  characters  (placed  there  with  the  %_
       sequence), then the newlines are treated as the beginnings of new para-
       graphs,  and  the  $FirstIndent  indentation is used for the next line.
       You can use two consecutive newlines to have spaced paragraphs  emitted
       from a single reminder body.

       A  RUN-type reminder also passes the body through the substitution fil-
       ter, but then executes the result as  a  system  command.   A  CAL-type
       reminder  is  used  only to place entries in the calendar produced when
       Remind is run with the -c, -s or -p options.

       A PS or PSFILE-type reminder is used to pass PostScript  code  directly
       to  the  printer when producing PostScript calendars.  This can be used
       to shade certain calendar entries (see the psshade() function), include
       graphics in the calendar, or almost any other purpose you can think of.
       You should not use these types of reminders unless you  are  an  expert
       PostScript  programmer.  The PS and PSFILE reminders are ignored unless
       Remind is run with the -p option.  See the section  "More  about  Post-
       Script" for more details.

       A  SPECIAL-type reminder is used to pass "out-of-band" information from
       Remind to a calendar-producing back-end.  It should be  followed  by  a
       word  indicating  the type of special data being passed.  The type of a
       special reminder depends on the back-end.   For  the  Rem2PS  back-end,
       SPECIAL  PostScript  is  equivalent  to a PS-type reminder, and SPECIAL
       PSFile is equivalent to a PSFILE-type reminder.  The body of a  SPECIAL
       reminder  is  obviously  dependent  upon the back-end.  A back-end must
       ignore a SPECIAL that it does not recognize.

       DATE SPECIFICATIONS

       A date_spec consists of zero to four parts.  These parts are  day  (day
       of month), month (month name), year and weekday.  Month and weekday are
       the English names of months and weekdays.  At  least  the  first  three
       characters  must  be  used.   The following are examples of the various
       parts of a date_spec:

       day:   1, 22, 31, 14, 3

       month: JANUARY, feb, March, ApR, may, Aug

       year:  1990, 1993, 2030.  The year can range from 1990 to 2075.

       weekday:
              Monday, tue, Wed, THU, Friday, saturday, sundAy

       Note that there can be several weekday components separated  by  spaces
       in a date_spec.

       INTERPRETATION OF DATE SPECIFICATIONS

       The following examples show how date specifications are interpreted.

       1.  Null date specification - the reminder is triggered every day.  The
       trigger date for a specific run is simply the current system date.

       2. Only day present.  The reminder is triggered on the specified day of
       each  month.  The trigger date for a particular run is the closest such
       day to the current system date.  For example:

            REM 1 MSG First of every month.
            REM 31 MSG 31st of every month that has 31 days.

       3. Only month present.  The reminder is  triggered  every  day  of  the
       specified month.  Example:

            REM Feb MSG Every day in February

       4.  day and month present.  Examples:

            REM 6 Jan MSG Every 6th of January
            REM Feb 29 MSG Every 29th of February

       5.  Only year present. Example:

            REM 1991 MSG Every day in 1991

       6.  year and day present.  Examples:

            REM 1 1990 MSG 1st of every month in 1990
            REM 1992 23 MSG 23rd of every month in 1992

       7.  year and month present.  Examples:

            REM Feb 1991 MSG Every day in Feb 1991
            REM 1992 September MSG Every day in Sept 1992

       8.  year, month and day present.  Examples:

            REM 8 Jan 1991 MSG 8th January 1991.
            REM 1992 March 9 MSG 9th March 1992.

       9.  weekday only.  Examples:

            REM Sat MSG Every Saturday
            REM Mon Tue Wed Thu Fri MSG Every working day
            REM Monday Wednesday MSG Every Monday and Wednesday

       10.  weekday and day present.  Examples:

            REM Sat 1 MSG First Saturday of every month
            REM Mon Tue Wed Thu Fri 15 \
                 MSG 1st working day on or after 15th of every month

       11.  weekday and month present.  Examples:

            REM Mon March MSG Every Monday in March
            REM Mon Tue Wed Thu Fri Feb MSG Every working day in February

       12.  weekday, month and day present.  Examples:

            REM Mon 1 March MSG First Monday in March
            REM Sat Sun 15 July MSG First Sat or Sun on or after 15 July

       13.  weekday and year present.  Example:

            REM Sat Sun 1991 MSG Every Saturday and Sunday in 1991

       14.  weekday, day and year present.  Examples:

            REM Mon 15 1990 MSG 1st Mon after 15th of every month in 1990
            REM Mon Tue Wed Thu Fri 1 1990 \
                 MSG 1st working day of every month in 1990

       15.  weekday, month and year present.  Example:

            REM Mon Wed 1991 Feb MSG Every Mon and Wed in Feb 1991.

       16.  weekday, day, month and year present.  Example:

            REM Mon Tue Wed Thu Fri 28 Oct 1990 \
                 MSG 1st working day on or after 28 October 1990.

       Note  that  when both weekday and day are specified, Remind chooses the
       first date on or after the specified day that also satisfies the  week-
       day constraint.  It does this by picking the first date on or after the
       specified day that is listed in the list of weekdays.  Thus, a reminder
       like:

            REM Mon Tue 28 Oct 1990 MSG Hi

       would  be  issued  only  on  Monday, 29 October, 1990.  It would not be
       issued on Tuesday, 30 October, 1990, since the 29th is the  first  date
       to satisfy the weekday constraints.

       SHORT-HAND DATE SPECIFICATIONS

       In addition to spelling out the day, month and year separately, you can
       specify YYYY-MM-DD or YYYY/MM/DD.  For example,  the  following  state-
       ments are equivalent:

            REM 5 June 2010 MSG Cool!
            REM 2010-06-05  MSG Cool!

       You can also specify a date and time as YYYY-MM-DD@HH:MM.  These state-
       ments are equivalent:

            REM 19 Dec 2010 AT 16:45 MSG Hi
            REM 2010-12-19@16:45 MSG Hi

       There's one subtlety with short-hand date specifications:  The  follow-
       ing statements are not equivalent:

            REM 19 Dec 2010 AT 16:45 +60 MSG Hi
            REM 2010-12-19@16:45 +60 MSG Hi

       In  the second statement, the "+60" is a delta that applies to the date
       rather than a tdelta that applies to the time.  We recommend explicitly
       using the AT keyword with timed reminders.

       THE REMIND ALGORITHM

       Remind uses the following algorithm to compute a trigger date: Starting
       from the current date, it examines each day, one at a  time,  until  it
       finds a date that satisfies the date specification, or proves to itself
       that no such date exists.  (Actually, Remind merely behaves  as  if  it
       used  this  algorithm;  it  would be much too slow in practice.  Inter-
       nally, Remind uses much faster techniques to calculate a trigger date.)
       See DETAILS ABOUT TRIGGER COMPUTATION for more information.

       BACKWARD SCANNING

       Sometimes,  it  is necessary to specify a date as being a set amount of
       time before another date.  For example, the  last  Monday  in  a  given
       month  is computed as the first Monday in the next month, minus 7 days.
       The back specification in the reminder is used in this case:

            REM Mon 1 -7 MSG Last Monday of every month.

       A back is specified with one or two  dashes  followed  by  an  integer.
       This  causes Remind to move "backwards" from what would normally be the
       trigger date.  The difference between --7 and -7 will be explained when
       the OMIT keyword is described.

       ADVANCE WARNING

       For some reminders, it is appropriate to receive advance warning of the
       event.  For example, you may wish to be reminded of someone's  birthday
       several days in advance.  The delta portion of the REM command achieves
       this.  It is specified as one or two "+" signs followed by a number  n.
       Again,  the difference between the "+" and "++" forms will be explained
       under the OMIT keyword.  Remind will trigger the reminder  on  computed
       trigger  date, as well as on each of the n days before the event.  Here
       are some examples:

            REM 6 Jan +5 MSG Remind me of birthday 5 days in advance.

       The above example would be triggered every 6th of January, as  well  as
       the 1st through 5th of January.

       PERIODIC REMINDERS

       We  have  already  seen  some  built-in mechanisms for certain types of
       periodic reminders.  For example, an event  occurring  every  Wednesday
       could be specified as:

            REM Wed MSG Event!

       However,  events  that  do  not repeat daily, weekly, monthly or yearly
       require another approach.  The repeat  component  of  the  REM  command
       fills  this need.  To use it, you must completely specify a date (year,
       month and day, and optionally weekday); this is the start date  of  the
       repetition  period.   The repeat component is an asterisk followed by a
       number specifying the repetition period in days.

       For example, suppose you get paid every second Wednesday, and your last
       payday was Wednesday, 28 October, 1992.  You can use:

            REM 28 Oct 1992 *14 MSG Payday

       This issues the reminder every 14 days, starting from 28 Oct 1992.  You
       can use delta and back with repeat.  Note, however, that  the  back  is
       used  only  to  compute  the  starting  date;  thereafter, the reminder
       repeats with the specified period.  Similarly, if you specify  a  week-
       day,  it  is  used  only  to  calculate the starting date, and does not
       affect the repetition period.

       SCANFROM and FROM

       The SCANFROM and FROM keywords  are  for  advanced  Remind  programmers
       only,  and will be explained in the section "DETAILS ABOUT TRIGGER COM-
       PUTATION" near the end of this manual.  Note that SCANFROM is available
       only  in  versions  of Remind from 03.00.04 up.  FROM is available only
       from 03.01.00 and later.

       PRIORITY

       The PRIORITY keyword must be followed by a number from 0 to  9999.   It
       is  used in calendar mode and when sorting reminders.  If two reminders
       have the same trigger date and time, then they are sorted by  priority.
       If  the PRIORITY keyword is not supplied, a default priority of 5000 is
       used.  (This default can be changed by adjusting  the  system  variable
       $DefaultPrio.   See  the  section  "SYSTEM VARIABLES" for more informa-
       tion.)

       EXPIRY DATES

       Some reminders should be issued periodically for a  certain  time,  but
       then  expire.   For example, suppose you have a class every Friday, and
       that your last class is on 11 December 1992.  You can use:

            REM Fri UNTIL 11 Dec 1992 MSG Class today.

       Another example:  Suppose you have jury  duty  from  30  November  1992
       until  4  December 1992.  The following reminder will issue the message
       every day of your jury duty, as well as 2 days ahead of time:

            REM 1992-11-30 *1 +2 UNTIL 1992-12-04 MSG Jury duty

       Note that the repeat of *1 is necessary; without it, the reminder would
       be issued only on 30 November (and the two days preceding.)

       As  a  special  case, you can use the THROUGH keyword instead of *1 and
       UNTIL.  The following two REM commands are equivalent:

            REM 1992-11-30 *1 +2 UNTIL 1992-12-04 MSG Jury duty

            REM 1992-11-30 +2 THROUGH 1992-12-04 MSG Jury duty

       If you have an expiry date via the use of THROUGH or UNTIL, then Remind
       will never trigger the reminder after the expiry date.  For example, if
       you have this:

               OMIT 2021-01-08
               REM 2021-01-01 THROUGH 2021-01-08 AFTER MSG Test

       the reminder will not be triggered on 2021-01-08, and nor  will  it  be
       triggered  on  2021-01-09; even though the AFTER keyword would normally
       move the 8th's reminder to the 9th, the expiry date of 2021-01-08 over-
       rides that.

       THE ONCE KEYWORD

       Sometimes,  it  is necessary to ensure that reminders are run only once
       on a given day.  For example, if you  have  a  reminder  that  makes  a
       backup of your files every Friday:

            REM Fri RUN do_backup

       (Here,  do_backup  is assumed to be a program or shell script that does
       the work.)  If you run Remind from your .login script, for example, and
       log  in  several  times per day, the do_backup program will be run each
       time you log in.   If,  however,  you  use  the  ONCE  keyword  in  the
       reminder,  the  Remind  checks  the  last  access  date of the reminder
       script.  If it is the same as the current date, Remind assumes that  it
       has  already been run, and will not issue reminders containing the ONCE
       keyword.

       Note that if you view or edit your reminder  script,  the  last  access
       date  will  be updated, and the ONCE keyword will not operate properly.
       If you start Remind with the -o option, then the ONCE keyword  will  be
       ignored.

       LOCALLY OMITTING WEEKDAYS

       The OMIT portion of the REM command is used to "omit" certain days when
       counting the delta or back.  It is specified  using  the  keyword  OMIT
       followed  by  a  list of weekdays.  Its action is best illustrated with
       examples:

            REM 1 +1 OMIT Sat Sun MSG Important Event

       This reminder is normally triggered on the first  of  every  month,  as
       well as the day preceding it.  However, if the first of the month falls
       on a Sunday or Monday, then the reminder is triggered starting from the
       previous Friday.  This is because the delta of +1 does not count Satur-
       day or Sunday when it counts backwards from the trigger date to  deter-
       mine how much advance warning to give.

       Contrast  this  with  the  use  of "++1" in the above command.  In this
       case, the reminder is triggered on the first of each month, as well  as
       the day preceding it.  The omitted days are counted.

            REM 1 -1 OMIT Sat Sun MSG Last working day of month

       Again, in the above example, the back of -1 normally causes the trigger
       date to be the last day of the month.  However,  because  of  the  OMIT
       clause,  if  the  first  of  the month falls on a Sunday or Monday, the
       trigger date is moved backwards past the weekend to  Friday.   (If  you
       have  globally  omitted  holidays, the reminder will be moved back past
       them, also.  See "The OMIT command" for more details.)

       By comparison, if we had used "--1", the reminder would be triggered on
       the last day of the month, regardless of the OMIT.

       COMPUTED LOCAL OMITS

       The  OMITFUNC phrase of the REM command allows you to supply a function
       that determines whether or not a date  is  omitted.   The  function  is
       passed  a  single  parameter  of  type DATE, and must return a non-zero
       integer if the date is considered "omitted" and 0 otherwise.  Here's an
       example:

               FSET _third(x) (day(x) % 3) || \
                              (wkdaynum(x) == 0) || \
                              (wkdaynum(x) == 6)
               REM OMITFUNC _third AFTER MSG Working day divisible by 3

       In  the example above, the reminder is triggered every Monday to Friday
       whose day-of-month number is divisible by three.  Here's how it works:

       o      The OMITFUNC _third portion causes all days for which  _third(x)
              returns  non-zero  to  be considered "omitted".  This causes all
              days whose day-of-month number is not a multiple of three to  be
              omitted.   Note that _third also returns non-zero if the weekday
              is Sunday or Saturday.

       o      The AFTER keyword causes the reminder to be moved after a  block
              of omitted days.

       The combination of OMITFUNC and AFTER keyword causes the reminder to be
       issued on all days whose day-of-month number is divisible by three, but
       not on Saturday or Sunday.

       Note  that if you use OMITFUNC, then a local OMIT is ignored as are all
       global OMITs.  If you want to omit specific weekdays, your  omit  func-
       tion will need to test for them specifically.  If you want to take into
       account the global OMIT context, then your omit function will  need  to
       test for that explicitly (using the isomitted() function.)

       Note  that  an incorrect OMITFUNC might cause all days to be considered
       omitted.  For that reason, when Remind searches through  omitted  days,
       it  terminates  the  search after the SATISFY iteration limit (command-
       line option -x.)

       ADDING TRIGGER DATES TO THE OMIT CONTEXT

       If the ADDOMIT keyword appears in a REM command, then the trigger  date
       (if  one  could  be  calculated)  is automatically added to the list of
       global OMITs.

       The command:

               REM ... whatever ... ADDOMIT MSG Foo

       is identical in behaviour to the sequence:

               REM ... whatever ... SATISFY 1
               IF trigvalid()
                   OMIT [trigdate()] MSG Foo
               ENDIF

       TIMED REMINDERS

       Timed reminders are those that have an AT keyword followed  by  a  time
       and  optional tdelta and trepeat.  The time may be specified in 24-hour
       format, with 0:00 representing midnight, 12:00 representing  noon,  and
       23:59  representing  one  minute to midnight.  Alternatively, it may be
       specified in common "AM/PM" format; in this case, the hour  must  range
       from  1  to  12.  12:00am represents midnight, 12:00pm represents noon,
       and 11:59pm represents one minute to midnight.  The "am" and "pm"  por-
       tions are case-insensitive and the "m" is optional.

       You  can  use either a colon or a period to separate the hours from the
       minutes.  That is, 13:39 and 13.39 are equivalent.

       Remind treats timed reminders specially.  If the  trigger  date  for  a
       timed  reminder is the same as the current system date, the reminder is
       queued for later activation.  When Remind has finished  processing  the
       reminder  file,  it  puts itself in the background, and activates timed
       reminders when the system time reached the specified time.


       If the trigger date is not the same as the system date, the reminder is
       not queued.

       For  example, the following reminder, triggered every working day, will
       emit a message telling you to leave at 5:00pm:

            REM Mon Tue Wed Thu Fri AT 17:00 MSG Time to leave!

       The following reminder will be triggered on Thursdays and Fridays,  but
       will only be queued on Fridays:

            REM Fri ++1 AT 1:00PM MSG Lunch at 1pm Friday.

       The  tdelta  and  trepeat have the same form as a repeat and delta, but
       are specified in minutes.  For example, this reminder will be triggered
       at 12:00pm as well as 45 minutes before:

            REM AT 12:00 +45 MSG Example

       The  following  will be issued starting at 10:45, every half hour until
       11:45, and again at noon.

            REM AT 12:00 +75 *30 MSG Example2

       The "+75" means that the reminder is issued starting 75 minutes  before
       noon; in other words, at 10:45.  The *30 specifies that the reminder is
       subsequently to be issued every 30 minutes.  Note that the reminder  is
       always issued at the specified time, even if the tdelta is not a multi-
       ple of the trepeat.   So  the  above  example  is  issued  at  10:45am,
       11:15am,  11:45am,  and  12:00pm.  Note that in the time specification,
       there is no distinction between the "+" and "++" forms of tdelta.

       Normally, Remind  will  issue  timed  reminders  as  it  processes  the
       reminder script, as well as queuing them for later.  If you do not want
       Remind to issue the reminders when processing the script, but  only  to
       queue  them  for  later, use the -a command-line option.  If you do not
       want reminders to be queued for later, use the -q command-line  option.

       Normally, Remind forks a background process to handle queued reminders.
       If you want Remind to remain in the foreground, use the -f command-line
       option.   This  is  useful, for example, in .xinitrc scripts, where you
       can use the command:

            remind -fa myreminders &

       This ensures that when  you  exit  X-Windows,  the  Remind  process  is
       killed.

       WARNING ABOUT TIMED REMINDERS

       Note:  If you use user-defined functions or variables (described later)
       in the bodies of timed reminders, then when  the  timed  reminders  are
       activated,  the  variables and functions have the definitions that were
       in effect at the end of the reminder script.  These definitions may not
       necessarily  be  those that were in effect at the time the reminder was
       queued.

       THE SCHED AND WARN KEYWORDS

       The SCHED keyword allows more precise control over  the  triggering  of
       timed  reminders,  and the WARN keyword allows precise control over the
       advance triggering of all types of reminders.  However, discussion must
       be  deferred  until  after  expressions  and user-defined functions are
       explained.  See the subsection "PRECISE SCHEDULING" further on.

       TAG AND DURATION

       The TAG keyword lets you "tag" certain  reminders.   This  facility  is
       used by certain back-ends or systems built around Remind, such as TkRe-
       mind.  These back-ends have specific rules about tags; see their  docu-
       mentation for details.

       The TAG keyword is followed by a tag consisting of up to 48 characters.
       You can have as many TAG clauses as you like in a given REM  statement.

       If  you  supply the -y option to Remind, then any reminder that lacks a
       TAG will have one synthesized.  The synthesized  tag  consists  of  the
       characters  "__syn__" followed by the hexadecimal representation of the
       MD5 sum of the REM command line.  This lets  you  give  a  more-or-less
       unique identifier to each distinct REM command.

       The DURATION keyword makes sense only for timed reminders; it specifies
       the duration of an event.  For example, if you have a 90-minute meeting
       starting at 1:00pm, you could use any of the following:

            REM 5 March 2021 AT 13:00 DURATION 1:30 MSG Meeting
            REM 5 March 2021 AT 13:00 DURATION 90 MSG Meeting
            REM 5 March 2021 AT 1:00pm DURATION 1:30 MSG Meeting
            REM 5 March 2021 AT 1:00pm DURATION 90 MSG Meeting


       Note  that duration is specified either in hours and minutes as a time,
       or in minutes as an integer.  If you specify a duration of 00:00 or  0,
       then  Remind behaves exactly as if no DURATION at all had been present.




SYNTACTIC SUGAR FOR REM

       The  REM  command  has  syntactic  sugar  to  let  you  express  common
       reminders.  The following pairs of reminders are equivalent:

           REM First Monday April MSG Foo
           REM Mon 1 April        MSG Foo

           REM Second Monday May  MSG Bar
           REM Mon 8 May          MSG Bar

           REM Third Monday MSG Third Monday of every month
           REM Mon 15 MSG Third Monday of every month

           REM Fourth Sunday June 2025 MSG Fourth Sunday in June 2025
           REM Sun 22 June 2025 MSG Fourth Sunday in June 2025

           REM Last Monday MSG Last Monday of every month
           REM Mon 1 --7 MSG Last Monday of every month

           REM Last Monday April MSG Last Monday of every April
           REM Mon 1 May --7 MSG  Last Monday of every April

           REM Last Monday December 2025 MSG Last Monday of Dec 2025
           REM Monday 1 Jan 2026 --7 MSG Last Monday of Dec 2025

       Note that Last effectively adjusts the month and year, if necessary, to
       make the reminder trigger on the correct date.

       The keyword IN is completely ignored, so you can write (for example):

           REM Second Monday in May MSG foo
           REM Last Monday in December 2025 MSG Bar

       An alternate form of back makes writing reminders easier.  The  follow-
       ing groups of reminders are equivalent:

           REM ~~1 MSG Last day of every month
           REM Lastday MSG  Last day of every month
           REM 1 --1 MSG Last day of every month

           REM May ~~1 MSG Last day of May
           REM Lastday May MSG Last day of May
           REM 1 June --1 MSG Last day of May

           REM Dec 2025 ~~1 MSG Last day of December 2025
           REM Lastday Dec 2025 MSG Last day of December 2025
           REM 1 Jan 2026 --1 MSG Last day of December 2025

           REM Apr ~1 OMIT SAT SUN MSG Last workday of April
           REM Lastworkday April OMIT SAT SUN MSG Last workday of April
           REM 1 May -1 OMIT SAT SUN MSG Last workday of April

           REM Apr ~~7 MSG Seventh-last day of April
           REM 1 May --7 MSG Seventh-last day of April

           REM Apr ~2 OMIT SAT SUN MSG Second-last workday of April
           REM 1 May -2 OMIT SAT SUN MSG Second-last workday of April

       As we see, "Lastday" is equivalent to ~~1 and "Lastworkday" to ~1.

       Note  that the First/Second/Third/Fourth/Last keywords and the ~ and ~~
       form of back imply a value for the day of the month; as such, they can-
       not    be    combined    with    a   day.    Additionally,   First/Sec-
       ond/Third/Fourth/Last must have at least one weekday name.  The follow-
       ing are illegal:

           REM First Monday 3 June MSG Huh?
           REM April 3 ~~1 MSG What?
           REM Second June MSG Where's the weekday???



THE SUBSTITUTION FILTER

       Before  being  processed, the body of a REM command is passed through a
       substitution filter.  The filter scans for sequences "%x" (where "x" is
       any  letter and certain other characters) and performs substitutions as
       shown below.  (All dates refer to the trigger date of the reminder.)

       %a     is replaced with "on weekday, day month, year"
              For example, consider the reminder:

              REM 18 Oct 1990 +4 MSG Meeting with Bob %a.

              On 16 October 1990, it would print "Meeting with Bob  on  Thurs-
              day, 18 October, 1990."

              On  17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %b     is replaced with "in diff day's time" where diff is  the  actual
              number  of  days  between the current date and the trigger date.
              (OMITs have no effect.)
              For example, consider:

              REM 18 Oct 1990 +4 MSG Meeting with Bob %b.

              On 16 October 1990, it would print "Meeting with Bob in 2  days'
              time."

              On  17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %c     is replaced with "on weekday"
              Example: REM 18 Oct 1990 +4 MSG Meeting with Bob %c.

              On 16 October 1990, it would print "Meeting with Bob  on  Thurs-
              day."

              On  17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %d     is replaced with "day", the day of the month.

       %e     is replaced with "on dd-mm-yyyy"

       %f     is replaced with "on mm-dd-yyyy"

       %g     is replaced with "on weekday, day month"

       %h     is replaced with "on dd-mm"

       %i     is replaced with "on mm-dd"

       %j     is replaced with "on weekday, month  day-th,  year"   This  form
              appends  the  characters  "st", "nd", "rd" or "th" to the day of
              the month, as appropriate.

       %k     is replaced with "on weekday, month day-th"

       %l     is replaced with "on yyyy-mm-dd"

       %m     is replaced with "month", the name of the month.

       %n     is replaced with the number (1 to 12) of the month.

       %o     is replaced with " (today)" if and only if  the  current  system
              date is the same as the date being used by Remind as the current
              date.  Recall that you can specify a date for Remind to  use  on
              the  command line.  This substitution is not generally useful in
              a REM command, but is useful in a  BANNER  command.   (See  "The
              BANNER Command.")

       %p     is  replaced  with  "s" if the diff between the current date and
              the trigger date is not  1.   You  can  use  this  to  construct
              reminders like:
              REM 1 Jan +4 MSG %x day%p to go before New Year!

       %q     is  replaced  with "'s" if the diff between the trigger date and
              the current date is 1.  Otherwise,  it  is  replaced  with  "s'"
              This can be used as follows:
              REM 1 Jan +4 MSG New Year in %x day%q time!

       %r     is  replaced  with the day of the month (01 to 31) padded with a
              leading zero if needed to pad to two digits.

       %s     is replaced with "st", "nd", "rd" or "th" depending on  the  day
              of the month.

       %t     is  replaced  with  the number of the month (01 to 12) padded to
              two digits with a leading zero.

       %u     is replaced with "on weekday, day-th month, year"  This is simi-
              lar  to  %a except that "st", "nd", "rd" or "th" is added to the
              day as appropriate.

       %v     is replaced with "on weekday, day-th month"

       %w     is replaced with "weekday", the name of the day of the week.

       %x     is replaced with the diff between the current date and the trig-
              ger  date.   The  diff  is  defined as the actual number of days
              between these two dates; OMITs are not  counted.   (Strict  date
              subtraction is performed.)

       %y     is replaced with "year", the year of the trigger date.

       %z     is replaced with "yy", the last two digits of the year.

       %_     (percent-underscore)  is  replaced  with a newline.  You can use
              this to achieve multi-line reminders.

       %1     is replaced with "now", "m minutes from now", "m  minutes  ago",
              "h  hours  from now", "h hours ago", "h hours and m minutes from
              now" or "h hours and m minutes ago", as appropriate for a  timed
              reminder.   Note  that  unless  you specify the -a option, timed
              reminders will be triggered like normal reminders,  and  thus  a
              timed  reminder  that  occurred  earlier in the day may be trig-
              gered.  This causes the need for the "...ago" forms.

       %2     is replaced with "at hh:mmam" or "..pm" depending on the AT time
              of the reminder.

       %3     is replaced with "at hh:mm" in 24-hour format.

       %4     is  replaced with "mm" where mm is the number of minutes between
              "now" and the time specified by AT.  If the AT time  is  earlier
              than the current time, then the result is negative.

       %5     is replaced with "ma" where ma is the absolute value of the num-
              ber produced by %4.

       %6     is replaced with "ago" or "from now", depending on the relation-
              ship between the AT time and the current time.

       %7     is replaced with the number of hours between the AT time and the
              current time.  It is always non-negative.

       %8     is replaced with the number of minutes between the AT  time  and
              the current time, after the hours (%7) have been subtracted out.
              This is a number ranging from 0 to 59.

       %9     is replaced with "s" if the value produced by %8 is not 1.

       %0     is replaced with "s" if the value produced by %7 is not 1.

       %!     is replaced with "is" if the current time is before the AT time,
              or "was" if it is after.

       %@     is similar to %2 but displays the current time.

       %#     is similar to %3 but displays the current time.

       %"     (percent-doublequote - ") is removed.  This sequence is not used
              by the substitution filter, but is used  to  tell  Remind  which
              text to include in a calendar entry when the -c, -s or -p option
              is chosen.  See "CALENDAR MODE"

       Notes:

       o      Remind normally prints a blank line after each reminder; if  the
              last  character  of  the body is "%", the blank line will not be
              printed.

       o      Substitutions a, b, c, e, f, g, h, i, j, k, l, u and v  all  are
              replaced  with  "today"  if  the current date equals the trigger
              date, or "tomorrow" if the trigger date is  one  day  after  the
              current  date.   Thus,  they  are  not the same as substitutions
              built up from the simpler %w, %y, etc.  sequences.

       o      The a, c, e, f, g, h, i, j, k, l, u, v, 2, and  3  substitutions
              may  be  preceded by an asterisk (for example, %*c) which causes
              the word "at" or "on" that would normally  be  included  in  the
              output to be omitted.

       o      Any of the substitutions dealing with time (0 through 9 and '!')
              produce undefined results if used in a reminder  that  does  not
              have  an AT keyword.  Also, if a reminder has a delta and may be
              triggered on several days, the  time  substitutions  ignore  the
              date.  Thus, the %1 substitution may report that a meeting is in
              15 minutes, for example, even though it may only be  in  2  days
              time,  because a delta has triggered the reminder.  It is recom-
              mended that  you  use  the  time  substitutions  only  in  timed
              reminders with no delta that are designed to be queued for timed
              activation.

       o      Capital letters can be used in  the  substitution  sequence,  in
              which case the first character of the substituted string is cap-
              italized (if it is normally a lower-case letter.)

       o      All other characters following a "%" sign are simply copied.  In
              particular,  to  get  a  "%" sign out, use "%%" in the body.  To
              start the body of a reminder with  a  space,  use  "%  ",  since
              Remind  normally scans for the first non-space character after a
              MSG, CAL or RUN token.


THE OMIT COMMAND

       In addition to being a keyword in the REM command, OMIT is a command in
       its own right.  Its syntax is:

              OMIT day month [year]

              or:

              OMIT day1 month1 year1 THROUGH day2 month2 year2

       The OMIT command is used to "globally" omit certain days (usually holi-
       days).  These globally-omitted days are skipped  by  the  "-"  and  "+"
       forms  of  back  and  delta,  but not by the "--" and "++" forms.  Some
       examples:

            OMIT 1 Jan
            OMIT 7 Sep 1992

       The first example specifies a holiday that occurs on the same date each
       year  -  New  Year's  Day.  The second example specifies a holiday that
       changes each year - Labour Day.  For these types of holidays, you  must
       create  an  OMIT  command for each year.  (Later, in the description of
       expressions and some of the more advanced features of Remind, you  will
       see how to automate this for some cases.)

       As  with  the  REM command, you can use shorthand specifiers for dates;
       the following are equivalent:

            OMIT 7 Sep 1992
            OMIT 1992-09-07

       For convenience, you can use a delta and MSG or RUN keyword in the OMIT
       command.  The following sequences are equivalent:

            OMIT 1 Jan
            REM 1 Jan +4 MSG New year's day is %b!

            and

            OMIT 1 Jan +4 MSG New year's day is %b!

       The  THROUGH  keyword  lets you conveniently OMIT a range of days.  The
       starting and ending points  must  be  fully-specified  (ie,  they  must
       include  day,  month  and year.).  For example, the following sequences
       are equivalent:

            OMIT 3 Jan 2011
            OMIT 4 Jan 2011
            OMIT 5 Jan 2011

            and

            OMIT 3 Jan 2011 THROUGH 5 Jan 2011

       You can make a THROUGH OMIT do double-duty as a REM command:

            OMIT 6 Sep 2010 THROUGH 10 Sep 2010 MSG Vacation


       You can debug your global OMITs with the following command:

            OMIT DUMP

       The OMIT DUMP command prints the current global omits to standard  out-
       put.

       THE BEFORE, AFTER AND SKIP KEYWORDS

       Normally,  days  that  are omitted, whether by a global OMIT command or
       the local OMIT or OMITFUNC keywords in a REM statement, only affect the
       counting  of  the -back or the +delta.  For example, suppose you have a
       meeting every Wednesday.  Suppose, too, that you have indicated 11  Nov
       as a holiday:

            OMIT 11 Nov +4 MSG Remembrance Day
            REM Wed +1 MSG Code meeting %b.

       The  above sequence will issue a reminder about a meeting for 11 Novem-
       ber 1992, which is a Wednesday.  This is probably incorrect.  There are
       three options:

       BEFORE This  keyword  moves  the  reminder  to before any omitted days.
              Thus, in the above example, use of BEFORE would cause the  meet-
              ing reminder to be triggered on Tuesday, 10 November 1992.

       AFTER  This  keyword  moves the reminder to after any omitted days.  In
              the above example, the meeting reminder would  be  triggered  on
              Thursday, 12 November 1992.

       SKIP   This keyword causes the reminder to be skipped completely on any
              omitted days.  Thus, in the above example,  the  reminder  would
              not  be  triggered  on  11  November 1992.  However, it would be
              triggered as usual on the following Wednesday, 18 November 1992.

       The  BEFORE  and  AFTER keywords move the trigger date of a reminder to
       before or after a block of omitted  days,  respectively.   Suppose  you
       normally  run  a backup on the first day of the month.  However, if the
       first day of the month is a weekend or holiday, you run the  backup  on
       the first working day following the weekend or holiday.  You could use:

            REM 1 OMIT Sat Sun AFTER RUN do_backup

       Let's examine how the trigger date is computed.  The  1  specifies  the
       first  day  of the month.  The local OMIT keyword causes the AFTER key-
       word to move the reminder forward past weekends.   Finally,  the  AFTER
       keyword  will  keep moving the reminder forward until it has passed any
       holidays specified with global OMIT commands.


THE DO AND INCLUDE COMMANDS

       Remind allows you to include other files in your reminder script, simi-
       lar to the C preprocessor #include directive.  For example, your system
       administrator may maintain a file of holidays or system-wide reminders.
       You can include these in your reminder script as follows:

            INCLUDE /usr/share/remind/holidays
            INCLUDE /usr/share/remind/reminders

       (The  actual  pathnames  vary  from  system to system - ask your system
       administrator.)

       INCLUDE files can be nested up to a depth of 8.

       If you specify a filename of "-" in the INCLUDE  command,  Remind  will
       begin reading from standard input.

       If you specify a directory as the argument to INCLUDE, then Remind will
       process all files in  that  directory  that  match  the  shell  patterm
       "*.rem".   The  files  are  processed  in  sorted order; the sort order
       matches that used by the shell when it expands "*.rem".

       Note that the file specified by an INCLUDE command is interpreted rela-
       tive  to  the  current working directory of the Remind process.  If you
       want to include a file relative to the directory  containing  the  cur-
       rently-processing  file,  use  DO instead.  For example, if the current
       file is /home/user/.reminders/foo.rem and Remind's working directory is
       /home/user, then:

           # Read /home/user/.reminders/bar.rem
           DO bar.rem

           # Read /usr/share/bar.rem - absolute path
           DO /usr/share/bar.rem

           # Read /home/user/bar.rem
           INCLUDE bar.rem

           # Read /usr/share/bar.rem - absolute path
           INCLUDE /usr/share/bar.rem

       Arguably,  the INCLUDE command should have worked the way DO does right
       from the start, but changing it would have broken  backward-compatibil-
       ity, hence the introduction of DO.



THE RUN COMMAND

       If  you include other files in your reminder script, you may not always
       entirely trust the contents of the other files.  For example, they  may
       contain  RUN-type  reminders that could be used to access your files or
       perform undesired actions.  The RUN command can restrict this:  If  you
       include  the  command  RUN  OFF  in your top-level reminder script, any
       reminder or expression that would normally execute a system command  is
       disabled.   RUN  ON  will  re-enable  the execution of system commands.
       Note that the RUN ON  command  can  only  be  used  in  your  top-level
       reminder  script; it will not work in any files accessed by the INCLUDE
       command.  This is to protect you from someone placing a RUN ON  command
       in  an  included file.  However, the RUN OFF command can be used at top
       level or in an included file.

       If you run Remind with the -r command-line option,  RUN-type  reminders
       and  the  shell() function will be disabled, regardless of any RUN com-
       mands in the reminder script.  However, any command supplied  with  the
       -k option will still be executed.

       One  use  of  the  RUN command is to provide a secure interface between
       Remind and the Elm mail system.  The Elm system can automatically  scan
       incoming  mail for reminder or calendar entries, and place them in your
       calendar file.  To use this feature, you should set the calendar  file-
       name  option under Elm to be something like "~/.reminders.in", not your
       main reminder file!  This is so that any RUN ON commands mailed to  you
       can never be activated.

       Then,  you can use the Elm scan message for calendar entries command to
       place reminders prefaced by "->"  into  .reminders.in.   In  your  main
       .reminders file, include the following lines:

            RUN OFF   # Disable RUN
            INCLUDE .reminders.in
            RUN ON    # Re-enable RUN

       In  addition,  Remind  contains a few other security features.  It will
       not read a file that is group- or world-writable.  It will not run set-
       uid.   If  it  reads  a file you don't own, it will disable RUN and the
       shell() function.  And if it is run as root, it will  only  read  files
       owned by root.

       Note  that if Remind reads standard input, it does not attempt to check
       the ownership of standard input, even if it is coming from a file,  and
       hence does not disable RUN and shell() in this situation.



THE INCLUDECMD COMMAND

       Remind allows you to execute a shell command and evaluate the output of
       that command as if it were an included file.  For  example,  you  could
       have scripts that extract reminders out of a database and print them on
       stdout as REM commands.  Here is an example:

            INCLUDECMD extract_reminders_for dfs

       We assume that the command "extract_reminders_for"  extracts  reminders
       out  of  a  central  database  for the named user.  Another use-case of
       INCLUDECMD is if you have your reminders stored in a file in some  non-
       Remind  format;  you can write a command that transforms them to Remind
       format and then Remind can  "include"  the  file  with  an  appropriate
       INCLUDECMD command.

       Note  that if RUN is disabled, then INCLUDECMD will fail with the error
       message "RUN disabled"

       INCLUDECMD passes the rest of the line to popen(3),  meaning  that  the
       command  is  executed  by the shell.  As such, shell metacharacters may
       need escaping or arguments quoting, depending on what you're trying  to
       do.   Remind  itself  does  not perform any modification of the command
       line (apart from the normal [expr] expression-pasting mechanism).

       If the command passed to INCLUDECMD begins  with  an  exclamation  mark
       "!",  then  Remind  disables RUN for the output of the command.  If you
       are running a command whose output you don't quite  trust,  you  should
       prefix it with "!" so that any RUN commands it emits fail.

       An  INCLUDECMD  command  counts towards the INCLUDE nesting depth.  For
       any given Remind run, a given INCLUDECMD command is only executed  once
       and  the  results are cached.  For example, if you generate a calendar,
       each unique INCLUDECMD command is run just once, not once for each  day
       of the produced calendar.  "Uniqueness" is determined by looking at the
       command that will be passed to the shell,  so  if  (for  example)  your
       INCLUDECMD  uses expression-pasting that results in differences depend-
       ing on the value of today(), then each unique version  of  the  command
       will be executed once.




THE BANNER COMMAND

       When Remind first issues a reminder, it prints a message like this:

            Reminders for Friday, 30th October, 1992 (today):

       (The  banner is not printed if any of the calendar-producing options is
       used, or if the -k option is used.)

       The BANNER command lets you change the format.  It should appear before
       any REM commands.  The format is:

              BANNER format

       The  format  is  similar  to  the  body of a REM command.  It is passed
       through the substitution filter, with an implicit trigger of  the  cur-
       rent system date.  Thus, the default banner is equivalent to:

            BANNER Reminders for %w, %d%s %m, %y%o:

       You can disable the banner completely with BANNER %.  Or you can create
       a custom banner:

            BANNER Hi - here are your reminders for %y-%t-%r:


CONTROLLING THE OMIT CONTEXT

       Sometimes, it is necessary to temporarily change the global OMITs  that
       are in force for a few reminders.  Three commands allow you to do this:

       PUSH-OMIT-CONTEXT
              This command saves the  current  global  OMITs  on  an  internal
              stack.

       CLEAR-OMIT-CONTEXT
              This  command  clears  all of the global OMITs, starting you off
              with a "clean slate."

       POP-OMIT-CONTEXT
              This command restores the global OMITs that were  saved  by  the
              most recent PUSH-OMIT-CONTEXT.

       For example, suppose you have a block of reminders that require a clear
       OMIT context, and that they also introduce unwanted global  OMITs  that
       could  interfere  with  later  reminders.   You could use the following
       fragment:

            PUSH-OMIT-CONTEXT   # Save the current context
            CLEAR-OMIT-CONTEXT  # Clean the slate
            # Block of reminders goes here
            POP-OMIT-CONTEXT    # Restore the saved omit context


EXPRESSIONS

       In certain contexts, to be described later, Remind will accept  expres-
       sions  for  evaluation.  Remind expressions resemble C expressions, but
       operate on different types of objects.

       DATA TYPES

       Remind expressions operate on five types of objects:

       INT    The INT data type consists of the integers representable in  one
              machine  word.   The  INT  data  type corresponds to the C "int"
              type.

       STRING The STRING data type consists of strings of characters.   It  is
              somewhat  comparable  to  a  C character array, but more closely
              resembles the string type in BASIC.

       TIME   The TIME data type consists of times of the day.  The TIME  data
              type  is internally stored as an integer representing the number
              of minutes since midnight.

       DATE   The DATE data type consists  of  dates  (later  than  1  January
              1990.)   Internally,  DATE  objects  are stored as the number of
              days since 1 January 1990.

       DATETIME
              The DATETIME data type consists of a  date  and  time  together.
              Internally, DATETIME objects are stored as the number of minutes
              since midnight, 1 January 1990.  You can  think  of  a  DATETIME
              object as being the combination of DATE and TIME parts.

       CONSTANTS

       The following examples illustrate constants in Remind expressions:

       INT constants
              12, 36, -10, 0, 1209

       STRING constants
              "Hello there", "This is a test", "\n\gosd\w", ""

              Note  that the empty string is represented by "", and that back-
              slashes in a string are not interpreted specially,  as  in  they
              are in C.

       TIME constants
              12:33, 0:01, 14:15, 16:42, 12.16, 13.00, 1.11, 4:30PM, 12:20am

              Note  that TIME constants may be written in 24-hour format or in
              common "AM/PM" format.  If you use "AM/PM" format, then the hour
              can range from 1 to 12.  Either a period or colon can be used to
              separate the minutes from the hours.  However, Remind will  con-
              sistently  output times in 24-hour format using only one separa-
              tor character.  (The output separator  character  is  chosen  at
              compile-time.)

       DATE constants
              DATE  constants  are  expressed as 'yyyy/mm/dd' or 'yyyy-mm-dd',
              and the single quotes must be supplied.  This distinguishes date
              constants from division or subtraction of integers.  Examples:

              '1993/02/22', '1992-12-25', '1999/01/01'

              Note  that DATE values are printed without the quotes.  Although
              either '-' or '/' is accepted as a date separator on input, when
              dates are printed, only one will be used.  The choice of whether
              to use '-' or '/' is made at compile-time.  Note also that  ver-
              sions  of  Remind  prior  to  03.00.01 did not support date con-
              stants.  In those versions, you  must  create  dates  using  the
              date()  function.  Also, versions prior to 03.00.02 did not sup-
              port the '-' date separator.

       DATETIME constants
              DATETIME constants are expressed  similarly  to  DATE  constants
              with  the  addition  of an "@HH:MM" part, optionally followed by
              "am" or "pm".  For example:

              '2008-04-05@23:11',   '1999/02/03@14:06',    '2001-04-07@08:30',
              '2020-01-01@3:20pm'

              DATETIME  values  are  printed  without the quotes.  Notes about
              date and time separator characters for DATE and  TIME  constants
              apply also to DATETIME constants.

       ZERO VALUES

       The  non-string  types  all  have  an  associated  zero value, which is
       treated as "false" by the IF command and the  logical  operators.   The
       zero values are:


              INT - 0

              DATE - '1990-01-01'

              TIME - 00:00

              DATETIME - '1990-01-01@00:00'

       Additionally,  for  the  purpose of the IF command (but not the logical
       operators) the empty string "" is considered a false value.

       OPERATORS

       Remind has the following operators.  Operators on the  same  line  have
       equal  precedence, while operators on lower lines have lower precedence
       than those on higher lines.  The operators approximately correspond  to
       C operators.

            !  -     (unary logical negation and arithmetic negation)
            *  /  %
            +  -
            <  <=  >  >=
            ==  !=
            &&
            ||

       DESCRIPTION OF OPERATORS


       !      Logical  negation.  Can be applied to an INT type.  If the oper-
              and is non-zero, returns zero.  Otherwise, returns 1.

       -      Unary minus.  Can be applied to an INT.  Returns the negative of
              the operand.

       *      Multiplication.  Returns the product of two INTs.

       /      Integer  division.  Returns the quotient of two INTs, discarding
              the remainder.

       %      Modulus.   Returns  the  remainder  upon  dividing  one  INT  by
              another.

       +      Has several uses.  These are:

              INT + INT - returns the sum of two INTs.

              INT + TIME or TIME + INT - returns a TIME obtained by adding INT
              minutes to the original TIME.  The result will always range from
              00:00 through 23:59.

              TIME + TIME treats the second TIME parameter as a duration, con-
              verting it to an integer number of minutes  past  midnight,  and
              then performs addition as with TIME + INT.

              INT + DATE or DATE + INT - returns a DATE obtained by adding INT
              days to the original DATE.

              INT + DATETIME or DATETIME + INT - returns a  DATETIME  obtained
              by adding INT minutes to the original DATETIME.

              DATETIME  + TIME or TIME + DATETIME treats the TIME parameter as
              a duration, converting it to an integer number of  minutes  past
              midnight, and then performs addition as with DATETIME + INT.

              STRING  + STRING - returns a STRING that is the concatenation of
              the two original STRINGs.

              STRING + anything or anything + STRING - converts the non-STRING
              argument  to a STRING, and then performs concatenation.  See the
              coerce() function.

       -      Has several uses.  These are:

              INT - INT - returns the difference of two INTs.

              DATE - DATE - returns (as an INT) the difference in days between
              two DATEs.

              TIME  -  TIME  -  returns  (as an INT) the difference in minutes
              between two TIMEs.

              DATETIME - DATETIME - returns (as an INT) the difference in min-
              utes between two DATETIMEs.

              DATE  -  INT  - returns a DATE that is INT days earlier than the
              original DATE.

              TIME - INT - returns a TIME that is INT minutes earlier than the
              original TIME.

              DATETIME  - INT - returns a DATETIME that is INT minutes earlier
              than the original DATETIME.

              DATETIME - TIME - coerces the TIME to an INT and  then  performs
              subtraction as above.

       <, <=, >, and >=
              These  are  the comparison operators.  They can take operands of
              any type, but both operands must be of the same type.  The  com-
              parison operators return 1 if the comparison is true, or 0 if it
              is false.  Note that string comparison  is  done  following  the
              lexical  ordering  of  characters on your system, and that upper
              and lower case are distinct for these operators.

       ==, != == tests for equality, returning 1 if its  operands  are  equal,
              and 0 if they are not.  != tests for inequality.

              If  the  operands  are not of the same type, == returns 0 and !=
              returns 1.  Again, string comparisons are case-sensitive.

       &&     This is the logical AND operator.  Both of its operands must  be
              of  the same type and must not be STRING type.  Returns the sec-
              ond operand if both operands are non-zero.  Otherwise, returns a
              zero of the same type as the operands.

       ||     This  is  the logical OR operator.  Both of its operands must be
              of the same type and must not be of STRING type.  It returns the
              first  operand that is non-zero; if both operands are zero, then
              returns a zero of the same type as the operands.

       NOTES

       If the result of an addition, subtraction or  multiplication  operation
       would  not  fit  in  a  C "int" type, Remind issues a "Number too high"
       error.  Unlike C, integer operations will not  simply  give  the  wrong
       answer in case of overflow.

       Operators  of equal precedence are always evaluated from left to right,
       except where parentheses dictate otherwise.  This is important, because
       the enhanced "+" operator is not necessarily associative.  For example:

            1 + 2 + "string" + 3 + 4  yields "3string34"
            1 + (2 + "string") + (3 + 4)  yields "12string7"
            12:59 + 1 + "test"  yields "13:00test"
            12:59 + (1 + "test")  yields "12:591test"

       The logical operators are not  so-called  short-circuit  operators,  as
       they  are  in C.  Both operands are always evaluated.  Thus, an expres-
       sion such as:

            (f!=0) && (100/f <= 3)

       will cause an error if f is zero.

       VARIABLES

       Remind allows you to assign values to variables.  The  SET  command  is
       used as follows:

       SET var expr

       Var  is  the name of a variable.  It must start with a letter or under-
       score, and consist only of letters, digits and underscores.   Only  the
       first 64 characters of a variable name are significant.  Variable names
       are not case sensitive; thus, "Afoo" and "afOo" are the same  variable.
       Examples:

            SET a 10 + (9*8)
            SET b "This is a test"
            SET mydir getenv("HOME")
            SET time 12:15
            SET date today()

       Note  that variables themselves have no type.  They take on the type of
       whatever you store in them.

       Variables set with SET or on  the  command-line  with  -ivar=expr  have
       global scope.

       To delete a variable, use the UNSET command:

       UNSET var [var...]

       For example, to delete all the variables declared above, use:

            UNSET a b mydir time date

       SYSTEM VARIABLES

       In  addition  to the regular user variables, Remind has several "system
       variables" that are used to query or control  the  operating  state  of
       Remind.   System variables are available starting from version 03.00.07
       of Remind.

       All system variables begin with a dollar sign '$'.  They can be used in
       SET commands and expressions just as regular variables can.  All system
       variables always hold values of a specified type.   In  addition,  some
       system  variables  cannot be modified, and you cannot create new system
       variables.  System variables can be initialized  on  the  command  line
       with  the -i option, but you may need to quote them to avoid having the
       shell interpret the dollar sign.  System variable names are  not  case-
       sensitive.

       The  following  system variables are defined.  Those marked "read-only"
       cannot be changed with the SET command.  All system variables hold val-
       ues of type INT, unless otherwise specified.

       $CalcUTC
              If 1 (the default), then Remind uses C library functions to cal-
              culate the number of minutes between local  and  Universal  Time
              Coordinated.   This affects astronomical calculations (sunrise()
              for example.)  If 0, then you must supply the number of  minutes
              between local and Universal Time Coordinated in the $MinsFromUTC
              system variable.

       $CalMode (read-only)
              If non-zero, then the -c option  was  supplied  on  the  command
              line.

       $Daemon (read-only)
              If  the  daemon mode -z was invoked, contains the number of min-
              utes between wakeups.  If not running in daemon  mode,  contains
              0.

       $DateSep
              This variable can be set only to "/" or "-".  It holds the char-
              acter used to separate portions of a date when Remind  prints  a
              DATE or DATETIME value.

       $DefaultColor
              This  variable can be set to a string that has the form of three
              space-separated numbers.  Each number must be an integer from  0
              to  255,  or all three numbers must be -1.  The default value of
              $DefaultColor is "-1 -1 -1", which suppresses  default  coloring
              of  MSG-type  reminders.   If you set $DefaultColor to any other
              value, then all MSG-, MSF- and  CAL-type  reminders  are  effec-
              tively  converted into SPECIAL COLOR reminders whose color value
              is specified by $DefaultColor.

              Unlike other system variables, the value of $DefaultColor is not
              preserved  between  calendar  iterations; rather, it is reset to
              "-1 -1 -1" at the start of each iteration.

       $DefaultPrio
              The default priority assigned to reminders  without  a  PRIORITY
              clause.   You  can set this as required to adjust the priorities
              of blocks of reminders without having  to  type  priorities  for
              individual  reminders.  At startup, $DefaultPrio is set to 5000;
              it can range from 0 to 9999.

       $DefaultTDelta
              The default time delta used if no +N is given in an  AT  clause.
              This  is  normally  0,  but  can  be  set with the -tt option or
              explicitly set in your script.  If  $DefaultDelta  is  non-zero,
              you  can use an explicit delta of +0 in an AT clause to counter-
              mand the default delta.

       $DontFork (read-only)
              If non-zero, then the -c option  was  supplied  on  the  command
              line.

       $DontTrigAts (read-only)
              The  number of times that the -a option was supplied on the com-
              mand line.

       $DontQueue (read-only)
              If non-zero, then the -q option  was  supplied  on  the  command
              line.

       $EndSent (STRING type)
              Contains a list of characters that end a sentence.  The MSF key-
              word inserts two  spaces  after  these  characters.   Initially,
              $EndSent is set to ".!?" (period, exclamation mark, and question
              mark.)

       $EndSentIg (STRING type)
              Contains a list of characters that should be  ignored  when  MSF
              decides  whether  or  not  to place two spaces after a sentence.
              Initially, is set to  "'>)]}"+CHAR(34)  (single-quote,  greater-
              than, right parenthesis, right bracket, right brace, and double-
              quote.)

              For example, the default values work as follows:

                   MSF He said, "Huh! (Two spaces will follow this.)"  Yup.

              because the final parenthesis and quote  are  ignored  (for  the
              purposes of spacing) when they follow a period.

       $FirstIndent
              The number of spaces by which to indent the first line of a MSF-
              type reminder.  The default is 0.

       $FoldYear
              The standard Unix library functions may have difficulty  dealing
              with  dates later than 2037.  If this variable is set to 1, then
              the UTC calculations "fold back" years later  than  2037  before
              using  the  Unix  library  functions.   For example, to find out
              whether or not daylight saving time is in effect in June,  2077,
              the year is "folded back" to 2010, because both years begin on a
              Monday, and both are non-leapyears.  The rules for daylight sav-
              ing  time  are thus presumed to be identical for both years, and
              the Unix library functions can handle 2010.   By  default,  this
              variable  is  0.  Set it to 1 if the sun or UTC functions misbe-
              have for years greater than 2037.

       $FormWidth
              The maximum width of each line of text for  formatting  MSF-type
              reminders.  The default is the width of the terminal in columns,
              minus 8, but clamped at a minimum of 20 and a  maximum  of  500.
              If  standard output is not a terminal, then the default is 72.If
              an MSF-type reminder contains a word too long  to  fit  in  this
              width,  it  will  not  be  truncated  -  the width limit will be
              ignored.

       $HushMode (read-only)
              If non-zero, then the -h option  was  supplied  on  the  command
              line.

       $IgnoreOnce (read-only)
              If  non-zero,  then  the  -o  option was supplied on the command
              line, or a date different from today's true date  was  supplied.
              If non-zero, then ONCE directives will be ignored.

       $InfDelta (read-only)
              If  non-zero,  then  the  -t  option was supplied on the command
              line.

       $IntMax (read-only)
              The largest representable INT.  On a machine with 32-bit  signed
              integers  using  twos-complement  representation,  this  will be
              2147483647.

       $IntMin (read-only)
              The smallest representable INT.  On a machine with 32-bit signed
              integers  using  twos-complement  representation,  this  will be
              -2147483648.

       $Latitude (STRING type)
              The latitude of your location, expressed as a string that  is  a
              floating-point  number.   Because  Remind does not have a native
              floating-point type, we need to express it as a string.   $Lati-
              tude  can  range  from  "-90.0" to "90.0", with positive numbers
              representing points north of the equator  and  negative  numbers
              representing south.  Note that regardless of your locale, $Lati-
              tude is always interpreted in the "C" locale and  as  such,  the
              decimal point must be a period (".").

       $Longitude (STRING type)
              The  longitude of your location, expressed as a string that is a
              floating-point number.  Because Remind does not  have  a  native
              floating-point type, we need to express it as a string.  $Longi-
              tude can range from "-180.0" to "180.0", with  positive  numbers
              representing  points east of the Greenwich Meridian and negative
              numbers representing west.  Note that regardless of your locale,
              $Longitude  is always interpreted in the "C" locale and as such,
              the decimal point must be a period (".").

              For example, the coordinates of the Statue  of  Liberty  in  New
              York City are approximately set by:

                      SET $Latitude   "40.68933"
                      SET $Longitude "-74.04454"

       $LatDeg, $LatMin, $LatSec (DEPRECATED)
              These  specify the latitude of your location.  $LatDeg can range
              from -90 to 90, and the others from -59 to 59.   Northern  lati-
              tudes  are  positive;  southern ones are negative.  For southern
              latitudes, all three components should be negative.  These three
              variables are deprecated; you should use $Latitude instead.

       $Location (STRING type)
              This  is  a  string specifying the name of your location.  It is
              usually the name of your town or city.  It can be set  to  what-
              ever  you  like, but good style indicates that it should be kept
              consistent with the latitude and longitude system variables.

       $LongDeg, $LongMin, $LongSec (DEPRECATED)
              These specify the longitude  of  your  location.   $LongDeg  can
              range  from -180 to 180.  Western longitudes are positive; east-
              ern ones are negative.  Note that all  three  components  should
              have  the same sign: All positive for western longitudes and all
              negative for eastern longitudes.  Note that for historical  rea-
              sons, the sign for longitude is different from the usual conven-
              tion!  If you find the longitude of your location from a  search
              engine,  you will most likely need to invert the sign to have it
              work correctly with Remind. These  three  variables  are  depre-
              cated;  you should use $Longitude instead.  Note also that $Lon-
              gitude uses the standard convention of negative for western lon-
              gitudes and positive for eastern ones.

              The latitude and longitude information is required for the func-
              tions sunrise() and sunset().  Default values  can  be  compiled
              into  Remind,  or you can SET the correct values at the start of
              your reminder scripts.

              Note that setting any of $LongDec, $LongMin and $LongSec updates
              $Longitude   correspondingly,  and  setting  $Longitude  updates
              $LongDeg, $LongMin and $LongSec.  Similar rules apply to  $Lati-
              tude, $LatDeg, $LatMin and $LatSec.

       $MaxSatIter
              The   maximum  number  of  iterations  for  the  SATISFY  clause
              (described later.)  Must be at least 10.

       $MaxStringLen
              A limit on the longest string that Remind will allow you to cre-
              ate.  The default is 65535.  If you set $MaxStringLen to 0 or to
              -1, then  remind  will  allow  you  to  create  arbitrarily-long
              strings, at least until it runs out of memory.

       $MinsFromUTC
              The  number  of  minutes  between Universal Time Coordinated and
              local time.  If $CalcUTC is non-zero, this  is  calculated  upon
              startup  of  Remind.  Otherwise, you must set it explicitly.  If
              $CalcUTC is zero, then $MinsFromUTC is used in the  astronomical
              calculations.  You must adjust it for daylight saving time your-
              self.  Also, if you want to initialize $MinsFromUTC using the -i
              command-line option, you must also set $CalcUTC to 0 with the -i
              option.

       $NextMode (read-only)
              If non-zero, then the -n option  was  supplied  on  the  command
              line.

       $NumQueued (read-only)
              Contains  the  number  of reminders queued so far for background
              timed triggering.

       $NumTrig (read-only)
              Contains the number of reminders triggered for the current date.
              One  use  for  this variable is as follows:  Suppose you wish to
              shade in the box of a PostScript calendar whenever a holiday  is
              triggered.   You  could  save the value of $NumTrig in a regular
              variable prior to executing a block of  holiday  reminders.   If
              the  value  of  $NumTrig after the holiday block is greater than
              the saved value, then at least one holiday  was  triggered,  and
              you  can execute the command to shade in the calendar box.  (See
              the section "Calendar Mode".)

              Note that $NumTrig is affected only by REM commands; triggers in
              IFTRIG commands do not affect it.

       $PrefixLineNo (read-only)
              If  non-zero,  then  the  -l  option was supplied on the command
              line.

       $PSCal (read-only)
              If non-zero, then the -p option  was  supplied  on  the  command
              line.

       $RunOff (read-only)
              If non-zero, the RUN directives are disabled.

       $SimpleCal (read-only)
              Set  to  a non-zero value if either of the -p or -s command-line
              options was supplied.

       $SortByDate (read-only)
              Set to 0 if no -g option is  used,  1  if  sorting  by  date  in
              ascending order, or 2 if sorting by date in descending order.

       $SortByPrio (read-only)
              Set  to  0  if no -g option is used, 1 if sorting by priority in
              ascending order, or 2  if  sorting  by  priority  in  descending
              order.

       $SortByTime (read-only)
              Set  to  0  if  no  -g  option  is used, 1 if sorting by time in
              ascending order, or 2 if sorting by time in descending order.

       $SubsIndent
              The number of spaces by which all lines (except the first) of an
              MSF-type reminder should be indented.  The default is 0.

       $SysInclude (read-only, STRING type)
              A  directory  path  containing  standard reminder scripts.  Cur-
              rently, Remind ships with some standard holiday files  and  lan-
              guage packs.  The value of $SysInclude is likely to be something
              like "/usr/share/remind" or "/usr/local/share/remind"

       $T (read-only, DATE type)
              Exactly equivalent to trigdate().  (See BUILT-IN FUNCTIONS.)

       $Td (read-only)
              Equivalent to day(trigdate()).

       $Tm (read-only)
              Equivalent to monnum(trigdate()).

       $Tw (read-only)
              Equivalent to wkdaynum(trigdate()).

       $Ty (read-only)
              Equivalent to year(trigdate()).

       $TimeSep
              This variable can be set only to ":" or ".".  It holds the char-
              acter  used  to separate portions of a time when Remind prints a
              TIME or DATETIME value.

       $UntimedFirst (read-only)
              Set to 1 if the -g option is used with a fourth  sort  character
              of "d"; set to 0 otherwise.

       $U (read-only, DATE type)
              Exactly equivalent to today().  (See BUILT-IN FUNCTIONS.)

       $Ud (read-only)
              Equivalent to day(today()).

       $Um (read-only)
              Equivalent to monnum(today()).

       $Uw (read-only)
              Equivalent to wkdaynum(today()).

       $Uy (read-only)
              Equivalent to year(today()).

       Note:   If  any of the calendar modes are in effect, then the values of
       $Daemon, $DontFork, $DontTrigAts, $DontQueue,  $HushMode,  $IgnoreOnce,
       $InfDelta, and $NextMode are not meaningful.

       BUILT-IN FUNCTIONS

       Remind has a plethora of built-in functions.  The syntax for a function
       call is the same as in C - the function name,  followed  a  comma-sepa-
       rated  list  of arguments in parentheses.  Function names are not case-
       sensitive.  If a function takes no arguments, it must  be  followed  by
       "()"  in  the  function call.  Otherwise, Remind will interpret it as a
       variable name, and probably not work correctly.

       In the descriptions below, short forms are used  to  denote  acceptable
       types  for  the  arguments.   The characters "i", "s", "d", "t" and "q"
       denote INT, STRING, DATE, TIME and  DATETIME  arguments,  respectively.
       If an argument can be one of several types, the characters are concate-
       nated.  For example, "di_arg" denotes an argument that can be a DATE or
       an INT.  "x_arg" denotes an argument that can be of any type.  The type
       of the argument is followed by an underscore and an  identifier  naming
       the argument.

       The built-in functions are:

       abs(i_num)
              Returns the absolute value of num.

       access(s_file, si_mode)
              Tests  the  access permissions for the file file.  Mode can be a
              string, containing a mix of the characters "rwx" for read, write
              and  execute  permission  testing.  Alternatively, mode can be a
              number as described in the  UNIX  access(2)  system  call.   The
              function  returns  0 if the file can be accessed with the speci-
              fied mode, and -1 otherwise.

       adawn([dq_date])
              Returns the time of "astronomical dawn" on the  specified  date.
              If  date  is omitted, defaults to today().  If a datetime object
              is supplied, only the date component is used.

       adusk([dq_date])
              Returns the time of "astronomical  twilight"  on  the  specified
              date.  If date is omitted, defaults to today().

       ampm(tq_time [,s_am [,s_pm]])
              Returns a STRING that is the result of converting time (which is
              either a TIME or a DATETIME  object)  to  "AM/PM"  format.   The
              optional arguments am and pm are the strings to append in the AM
              and PM case, respectively; they default to "AM" and  "PM".   The
              function  obeys  the  system  variables  $DateSep,  $TimeSep and
              $DateTimeSep when formatting its output.  For example:

                      ampm(0:22)                 returns "12:22AM"
                      ampm(17:45, "am", "pm")    returns "5:45pm"
                      ampm('2020-03-14@21:34')   returns "2020-03-14@9:34PM"


       args(s_fname)
              Returns the number of arguments  expected  by  the  user-defined
              function  fname,  or -1 if no such user-defined function exists.
              Note that this function examines  only  user-defined  functions,
              not built-in functions.  Its main use is to determine whether or
              not a particular user-defined function has been  defined  previ-
              ously.   The  args()  function  is available only in versions of
              Remind from 03.00.04 and up.

       asc(s_string)
              Returns an INT that is the ASCII code of the first character  in
              string.  As a special case, asc("") returns 0.

       baseyr()
              Returns  the "base year" that was compiled into Remind (normally
              1990.)  All dates are stored internally as the  number  of  days
              since 1 January of baseyr().

       char(i_i1 [,i_i2...])
              This  function can take any number of INT arguments.  It returns
              a STRING consisting of the characters  specified  by  the  argu-
              ments.   Note  that none of the arguments can be 0, unless there
              is only one argument.  As a special case, char(0) returns "".

              Note that because Remind does not support escaping of characters
              in strings, the only way to get a double-quote in a string is to
              use char(34).

       choose(i_index, x_arg1 [,x_arg2...])
              Choose must take at least two arguments, the first of  which  is
              an  INT.   If  index  is  n, then the nth subsequent argument is
              returned.  If index is less than 1, then arg1 is  returned.   If
              index  is  greater than the number of subsequent arguments, then
              the last argument is returned.  Examples:

                 choose(0, "foo", 1:13, 1000) returns "foo"
                 choose(1, "foo", 1:13, 1000) returns "foo"
                 choose(2, "foo", 1:13, 1000) returns 1:13
                 choose(3, "foo", 1:13, 1000) returns 1000
                 choose(4, "foo", 1:13, 1000) returns 1000
              Note that all arguments to choose() are always evaluated.

       coerce(s_type, x_arg)
              This function converts arg to the specified type, if  such  con-
              version  is  possible.   Type  must  be  one of "INT", "STRING",
              "DATE", "TIME" or "DATETIME" (case-insensitive).  The conversion
              rules are as follows:

              If  arg  is  already  of  the  type  specified,  it  is returned
              unchanged.

              If type is "STRING", then arg is converted to a string  consist-
              ing of its printed representation.

              If  type is "DATE", then an INT arg is converted by interpreting
              it as the number of days since 1 January baseyr().  A STRING arg
              is  converted  by  attempting to read it as if it were a printed
              date.  A DATETIME is converted to a date by  dropping  the  time
              component.  A TIME arg cannot be converted to a date.

              If  type is "TIME", then an INT arg is converted by interpreting
              it as the number of minutes since midnight.   A  STRING  arg  is
              converted by attempting to read it as if it were a printed time.
              A DATETIME is converted to a time by dropping  the  date  compo-
              nent.  A DATE arg cannot be converted to a time.

              If  type  is  "DATETIME", then an INT arg is converted by inter-
              preting it as the number of minutes since  midnight,  1  January
              baseyr().   A STRING is converted by attempting to read it as if
              it were a printed datetime.  Other types cannot be converted  to
              a datetime.

              If  type  is  "INT",  then DATE, TIME and DATETIME arguments are
              converted using the reverse of procedures  described  above.   A
              STRING arg is converted by parsing it as an integer.

       current()
              Returns  the  current  date and time as a DATETIME object.  This
              may be the actual date and time, or may be  the  date  and  time
              supplied on the command line.

       date(i_y, i_m, i_d)
              The  date()  function returns a DATE object with the year, month
              and day components specified by y, m and d.

       datepart(dq_datetime)
              Returns a DATE object representing the date portion of datetime.

       datetime(args)
              The datetime() function can take anywhere from two to five argu-
              ments.  It always returns a DATETIME generated  from  its  argu-
              ments.

              If  you  supply  two arguments, the first must be a DATE and the
              second a TIME.

              If you supply three arguments, the first must be a DATE and  the
              second  and  third must be INTs.  The second and third arguments
              are interpreted as hours and minutes and converted to a TIME.

              If you supply four arguments, the  first  three  must  be  INTs,
              interpreted  as  the  year,  month and day.  The fourth argument
              must be a TIME.

              Finally, if you supply five arguments, they must all be INTs and
              are interpreted as year, month, day, hour and minute.

       dawn([dq_date])
              Returns the time of "civil dawn" on the specified date.  If date
              is omitted, defaults to today().  If a datetime object  is  sup-
              plied, only the date component is used.

       day(dq_date)
              This  function  takes  a  DATE  or  DATETIME as an argument, and
              returns an INT that is the day-of-month component of date.

       daysinmon(i_m, i_y)
              Returns the number of days in month m (1-12) of the year y.

       defined(s_var)
              Returns 1 if the variable named by var is defined, or 0 if it is
              not.
              Note  that  defined() takes a STRING argument; thus, to check if
              variable X is defined, use:

                        defined("X")

              and not:

                        defined(X)

              The second example will attempt to evaluate X, and  will  return
              an error if it is undefined or not of type STRING.

       dosubst(s_str [,d_date [,t_time]]) or dosubst(s_str [,q_datetime])
              Returns  a  STRING that is the result of passing str through the
              substitution filter described earlier.  The parameters date  and
              time (or datetime) establish the effective trigger date and time
              used by the substitution filter.  If date and time are  omitted,
              they default to today() and now().

              Note that if str does not end with "%", a newline character will
              be added to the end of the result.  Also, calling dosubst() with
              a  date  that is in the past (i.e., if date < today()) will pro-
              duce undefined results.

              Dosubst() is only available starting from  version  03.00.04  of
              Remind.

       dusk([dq_date])
              Returns  the time of "civil twilight" on the specified date.  If
              date is omitted, defaults to today().

       easterdate(dqi_arg)
              If arg is an INT, then returns the date of Easter Sunday for the
              specified  year.  If arg is a DATE or DATETIME, then returns the
              date of the next Easter Sunday on or after arg.  (The time  com-
              ponent of a datetime is ignored.)

       evaltrig(s_trigger [,dq_start])
              Evaluates trigger as if it were a REM or IFTRIG trigger specifi-
              cation and returns the trigger date as a DATE (or as a  DATETIME
              if there is an AT clause.)  Returns a negative INT if no trigger
              could be computed.

              Normally, evaltrig finds a trigger date on or after  today.   If
              you  supply  the  start  argument,  then  it scans starting from
              there.

              For example, the expression:

                evaltrig("Mon 1", '2008-10-07')

              returns '2008-11-03', since that is the first date on or after 7
              October 2008 that satisfies "Mon 1".

              If  you want to see how many days it is from the first Monday in
              October, 2008 to the first Monday in November, 2008, use:

                evaltrig("Mon 1", '2008-11-01') - evaltrig("Mon 1", '2008-10-01')

              and the answer is 28.  The trigger argument to evaltrig can have
              all  the usual trigger clauses (OMIT, AT, SKIP, etc.) but cannot
              have a SATISFY, MSG, etc. reminder-type clause.

       filedate(s_filename)
              Returns the modification date of filename.  If filename does not
              exist,  or  its  modification  date is before the year baseyr(),
              then 1 January of baseyr() is returned.

       filedatetime(s_filename)
              Returns the modification date and time of filename.  If filename
              does  not  exist,  or  its  modification date is before the year
              baseyr(), then midnight, 1 January of baseyr() is returned.

       filedir()
              Returns the directory that contains the current file being  pro-
              cessed.  It may be a relative or absolute pathname, but is guar-
              anteed to be correct for use in an INCLUDE command as follows:

                 INCLUDE [filedir()]/stuff

              This includes the file "stuff" in the same directory as the cur-
              rent  file  being  processed.   Note  that this workaround is no
              longer necessary because DO stuff will achieve the same goal.

       filename()
              Returns (as a STRING) the name of the current  file  being  pro-
              cessed  by  Remind.   Inside included files, returns the name of
              the included file.

       getenv(s_envvar)
              Similar to the getenv(2) system call.  Returns a  string  repre-
              senting   the  value  of  the  specified  environment  variable.
              Returns "" if the environment variable  is  not  defined.   Note
              that  the names of environment variables are generally case-sen-
              sitive; thus, getenv("HOME") is not the same as  getenv("home").

       hebdate(i_day, s_hebmon [,idq_yrstart [,i_jahr [,i_aflag]]])
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hebday(dq_date)
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hebmon(dq_date)
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hebyear(dq_date)
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hour(tq_time)
              Returns the hour component of time.

       iif(si_test1, x_arg1, [si_test2, x_arg2,...], x_default)
              If  test1  is not zero or the null string, returns arg1.  Other-
              wise, if test2 is not zero or the null string, returns arg2, and
              so on.  If all of the test arguments are false, returns default.
              Note that all arguments are  always  evaluated.   This  function
              accepts  an odd number of arguments - note that prior to version
              03.00.05 of Remind, it accepted 3 arguments only.   The  3-argu-
              ment  version  of  iif() is compatible with previous versions of
              Remind.

       index(s_search, s_target [,i_start)
              Returns an INT that is the location  of  target  in  the  string
              search.  The first character of a string is numbered 1.  If tar-
              get does not exist in search, then 0 is returned.

              The optional parameter start specifies the position in search at
              which to start looking for target.

       isany(arg1 [,arg2, ..., argN]);
              Returns 1 if the first argument arg1 is equal to any of the sub-
              sequent arguments arg2 through argN; returns 0 otherwise.   Also
              returns 0 if called with only one argument.

              As an example, the following two expressions are equivalent:

                      (a == b) || (a == c) || (a == d) || (a == e)

                      isany(a, b, c, d, e)

       isdst([d_date [,t_time]]) or isdst(q_datetime)
              Returns  a  positive number if daylight saving time is in effect
              on the specified date and time.  Date defaults  to  today()  and
              time defaults to midnight.

              Note  that  this  function is only as reliable as the C run-time
              library  functions.   It  is  available  starting  with  version
              03.00.07 of Remind.

       isleap(idq_arg)
              Returns 1 if arg is a leap year, and 0 otherwise.  Arg can be an
              INT, DATE or DATETIME object.  If a DATE  or  DATETIME  is  sup-
              plied, then the year component is used in the test.

       isomitted(dq_date)
              Returns 1 if date is omitted, given the current global OMIT con-
              text.  Returns 0 otherwise.  (If a datetime  is  supplied,  only
              the  date  part  is used.)  Note that any local OMIT or OMITFUNC
              clauses are not taken into account by this function.

       language()
              Returns a STRING naming the language supported by Remind.   (See
              "SUPPORT FOR OTHER LANGUAGES") By default, Remind is compiled to
              support English messages, so this  function  returns  "English".
              For  other languages, this function will return the English name
              of the language (e.g. "German")  Note  that  language()  is  not
              available in versions of Remind prior to 03.00.02.

       lower(s_string)
              Returns  a  STRING with all upper-case characters in string con-
              verted to lower-case.

       max(x_arg1 [,x_arg2...)
              Can take any number of arguments, and returns the maximum.   The
              arguments  can be of any type, but must all be of the same type.
              They are compared as with the > operator.

       min(x_arg1 [,x_arg2...)
              Can take any number of arguments, and returns the minimum.   The
              arguments  can be of any type, but must all be of the same type.
              They are compared as with the < operator.

       minsfromutc([d_date [,t_time]]) or minsfromutc(q_datetime)
              Returns the number of minutes from  Universal  Time  Coordinated
              (formerly  GMT)  to  local  time on the specified date and time.
              Date defaults to today() and  time  defaults  to  midnight.   If
              local  time  is  before UTC, the result is negative.  Otherwise,
              the result is positive.

              Note that this function is only as reliable as  the  C  run-time
              library  functions.   It  is  available  starting  with  version
              03.00.07 of Remind.

       minute(tq_time)
              Returns the minute component of time.

       mon(dqi_arg)
              If arg is of DATE or DATETIME type, returns a string that  names
              the month component of the date.  If arg is an INT from 1 to 12,
              returns a string that names the month.

       monnum(dq_date)
              Returns an INT from 1 to 12, representing the month component of
              date.

       moondate(i_phase [,d_date [,t_time]]) or moondate(i_phase, q_datetime)
              This  function  returns  the date of the first occurrence of the
              phase phase of the moon on or after date and  time.   Phase  can
              range  from 0 to 3, with 0 signifying new moon, 1 first quarter,
              2 full moon, and 3  third  quarter.   If  date  is  omitted,  it
              defaults  to  today().   If time is omitted, it defaults to mid-
              night.

              For example, the following returns the date  of  the  next  full
              moon:

                        SET fullmoon moondate(2)


       moontime(i_phase [,d_date [,t_time]]) or moontime(i_phase, q_datetime)
              This  function  returns  the time of the first occurrence of the
              phase phase of the moon on or after date and  time.   Phase  can
              range  from 0 to 3, with 0 signifying new moon, 1 first quarter,
              2 full moon, and 3  third  quarter.   If  date  is  omitted,  it
              defaults  to  today().   If time is omitted, it defaults to mid-
              night.  Moontime() is intended to be used  in  conjunction  with
              moondate().   The  moondate() and moontime() functions are accu-
              rate to within a couple of minutes of the times in "Old Farmer's
              Almanac" for Ottawa, Ontario.

              For example, the following returns the date and time of the next
              full moon:

                        MSG Next full moon at [moontime(2)] on [moondate(2)]


       moondatetime(i_phase  [,d_date  [,t_time]])  or   moondatetime(i_phase,
       q_datetime)
              This function is similar to moondate and moontime, but returns a
              DATETIME result.

       moonphase([d_date [,t_time]]) or moonphase(q_datetime)
              This  function  returns  the phase of the moon on date and time,
              which  default  to  today()  and  midnight,  respectively.   The
              returned  value  is  an  integer from 0 to 359, representing the
              phase of the moon in degrees.  0 is a new moon, 180  is  a  full
              moon, 90 is first-quarter, etc.

       ndawn([dq_date])
              Returns  the  time of "nautical dawn" on the specified date.  If
              date is omitted, defaults to today().  If a datetime  object  is
              supplied, only the date component is used.

       ndusk([dq_date])
              Returns  the  time of "nautical twilight" on the specified date.
              If date is omitted, defaults to today().

       nonomitted(dq_start, dq_end [,s_wkday...])
              This function returns the number  of  non-omitted  days  between
              start  and  end.   If  start is non-omitted, then it is counted.
              end is never counted.

              Note that end must be greater than or equal to start or an error
              is  reported.  In addition to using the global OMIT context, you
              can supply additional arguments that are names of weekdays to be
              omitted.   However,  in a REM command, any local OMITFUNC clause
              is not taken into account by this function.

              For example, the following line sets a to 11 (assuming no global
              OMITs):

                   set a nonomitted('2007-08-01', '2007-08-16', "Sat", "Sun")

              because  Thursday,  16  August 2007 is the 11th working day (not
              counting Saturday and Sunday) after Wednesday, 1 August 2007.

              nonomitted has various uses.  For example, many schools run on a
              six-day cycle and the day number is not incremented on holidays.
              Suppose the school year starts with Day 1 on 4  September  2007.
              The following reminder will label day numbers in a calendar:

                 IF today() >= '2007-09-04'
                     set daynum nonomitted('2007-09-04', today(), "Sat", "Sun")
                     REM OMIT SAT SUN SKIP CAL Day [(daynum % 6) + 1]
                 ENDIF

              Obviously,  the  answer  you  get from nonomitted depends on the
              global OMIT context.  If you use moveable  OMITs,  you  may  get
              inconsistent results.

              Here  is  a more complex use for nonomitted.  My garbage collec-
              tion follows two interleaved 14-day cycles: One Friday,  garbage
              and  paper recycling ("Black Box") are collected.  The next Fri-
              day, garbage and plastic recycling ("Blue Box")  are  collected.
              If  any  of  Monday-Friday  is  a holiday, collection is delayed
              until the Saturday.  Here's a way to encode these rules:

                 fset _garbhol(x) wkdaynum(x) == 5 && nonomitted(x-4, x+1) < 5
                 REM 12 November 1999 *14 AFTER OMITFUNC _garbhol MSG Black Box
                 REM 19 November 1999 *14 AFTER OMITFUNC _garbhol MSG Blue Box

              Here's how it  works:   The  _garbhol(x)  user-defined  function
              returns  1  if and only if (1) x is a Friday and (2) there is at
              least one OMITted day from the previous Monday up to and includ-
              ing the Friday.

              The first REM statement sets up the 14-day black-box cycle.  The
              AFTER keyword makes it move collection to the Saturday if _garb-
              hol  returns  1.   The  second  REM statement sets up the 14-day
              blue-box cycle with a similar adjustment made by AFTER  in  con-
              junction with _garbhol.

       now()  Returns  the  current  system time, as a TIME type.  This may be
              the actual time, or a time supplied on the command line.

       ord(i_num)
              Returns a string that is the ordinal number num.   For  example,
              ord(2) returns "2nd", and ord(213) returns "213th".

       ostype()
              Returns "UNIX".  Remind used to run on OS/2 and MS-DOS, but does
              not any longer.

       pad(x_arg, s_padstr, i_len [, i_right])
              Converts the first argument arg to a string  if  necessary,  and
              then  if it is shorter than len characters, pads to to len char-
              acters using as many copies (including partial copies) of padstr
              as  necessary.   By  default,  the string is left-padded, but if
              right is supplied and non-zero, the string will be right-padded.

              Here are some examples:

                  pad(3, "0", 2)        -->  "03"
                  pad(465, "0", 2)      -->  "465"
                  pad("foo", " ", 5)    -->  "  foo"
                  pad("foo", " ", 5, 1) -->  "foo  "
                  pad("foo", "bar", 11) -->  "barbarbafoo"


       plural(i_num [,s_str1 [,s_str2]])
              Can  take  from one to three arguments.  If one argument is sup-
              plied, returns "s" if num is not 1, and "" if num is 1.

              If two arguments are supplied, returns str1 + "s" if num is  not
              1.  Otherwise, returns str1.

              If  three  arguments are supplied, returns str1 if num is 1, and
              str2 otherwise.

       psmoon(i_phase [,i_size [,s_note [,i_notesize]]])
              [DEPRECATED] Returns a STRING consisting of PostScript  code  to
              draw  a  moon in the upper-left hand corner of the calendar box.
              Phase specifies the phase of the moon, and is 0  (new  moon),  1
              (first quarter), 2 (full moon) or 3 (third quarter).  If size is
              specified, it controls the radius  of  the  moon  in  PostScript
              units  (1/72  inch.)  If it is not specified or is negative, the
              size of the day-number font is used.


              For example, the following four lines place moon symbols on  the
              PostScript calendar:

                        REM [moondate(0)] PS [psmoon(0)]
                        REM [moondate(1)] PS [psmoon(1)]
                        REM [moondate(2)] PS [psmoon(2)]
                        REM [moondate(3)] PS [psmoon(3)]

              If note is specified, the text is used to annotate the moon dis-
              play.  The font is the same font used for calendar entries.   If
              notesize  is  given,  it  specifies the font size to use for the
              annotation, in PostScript units (1/72 inch.)  If notesize is not
              given,  it  defaults to the size used for calendar entries.  (If
              you annotate the display, be careful not to  overwrite  the  day
              number  -- Remind does not check for this.)  For example, if you
              want the time of each new moon displayed, you could use this  in
              your reminder script:

                   REM [moondate(0)] PS [psmoon(0, -1, moontime(0)+"")]

              Note  how  the  time is coerced to a string by concatenating the
              null string.

       psshade(i_gray) or psshade(i_red, i_green, i_blue)
              [DEPRECATED] Returns a STRING that consists of  PostScript  com-
              mands to shade a calendar box.  Num can range from 0 (completely
              black) to 100 (completely white.)  If three arguments are given,
              they  specify  red,  green  and  blue  intensity  from 0 to 100.
              Here's an example of how to use this:

                        REM Sat Sun PS [psshade(95)]

              The above command emits PostScript code  to  lightly  shade  the
              boxes for Saturday and Sunday in a PostScript calendar.

              Note  that psmoon and psshade are deprecated; instead you should
              use the SPECIAL SHADE and SPECIAL MOON reminders as described in
              "Out-of-Band Reminders."

       realcurrent()
              Returns  (as  a  DATETIME) the true date and time of day as pro-
              vided by the operating system.  This  is  in  contrast  to  cur-
              rent(), which may return a time supplied on the command line.

       realnow()
              Returns  the  true time of day as provided by the operating sys-
              tem.  This is in contrast to now(), which may return a time sup-
              plied on the command line.

       realtoday()
              Returns  the  date as provided by the operating system.  This is
              in contrast to Remind's concept of "today", which may be changed
              if  it  is  running in calendar mode, or if a date has been sup-
              plied on the command line.

       sgn(i_num)
              Returns -1 if num is negative, 1 if num is positive,  and  0  if
              num is zero.

       shell(s_cmd [,i_maxlen])
              Executes  cmd  as  a  system  command, and returns the first 511
              characters of output resulting from cmd.  Any whitespace charac-
              ter in the output is converted to a space.  Note that if RUN OFF
              has been executed, or the -r command-line option has been  used,
              shell() will result in an error, and cmd will not be executed.

              If  maxlen  is  specified, then shell() returns the first maxlen
              characters of output (rather than the first 511).  If maxlen  is
              specified as a negative number, then it defaults to the value of
              the system variable $MaxStringLen.

       shellescape(s_str)
              Returns str with all shell metacharacters such as " ", "*",  etc
              escaped with a backslash.  For example:

               SET a shellescape("a b*? c&d$e")

              will set a to:

               "a\ b\*\?\ c\&d\$e"


       slide(d_start, i_amt [,s_wkday...])
              This  function  is  the inverse of nonomitted.  It adds amt days
              (which can be negative) to start,  not  counting  omitted  days.
              The  optional  wkday  arguments  are additional weekday names to
              omit.

              Consider this example:

                   OMIT 14 May 2009
                   SET a slide('2009-05-13', 5, "Sat", "Sun")

              In this case, a is set to 2009-05-21.  That's because  we  slide
              forward  by  5  days, not including Thursday, May 14 or Saturday
              and Sunday, May 16 and 17.  You can go backwards, too, so:

                   OMIT 14 May 2009
                   SET a slide('2009-05-21', -5, "Sat", "Sun")

              takes a back to 2009-05-13.

       strlen(s_str)
              Returns the length of str.  If the length of str is too large to
              represent as an integers, emits a "Number too high" error.

       substr(s_str, i_start [,i_end])
              Returns  a STRING consisting of all characters in str from start
              up to and including end.  Characters are numbered  from  1.   If
              end is not supplied, then it defaults to the length of str.

       sunrise([dq_date])
              Returns  a  TIME indicating the time of sunrise on the specified
              date (default today().)  In high latitudes, there may be no sun-
              rise  on  a  particular day, in which case sunrise() returns the
              INT 0 if the sun never sets, or 1440 if it never rises.

       sunset([dq_date])
              Returns a TIME indicating the time of sunset  on  the  specified
              date (default today().)  In high latitudes, there may be no sun-
              set on a particular day, in which case sunset() returns the  INT
              0 if the sun never rises, or 1440 if it never sets.

              The  functions  sunrise() and sunset() are based on an algorithm
              in "Almanac for Computers for the year 1978" by L.  E.  Doggett,
              Nautical  Almanac  Office,  USNO.  They require the latitude and
              longitude to be specified  by  setting  the  appropriate  system
              variables.   (See "System Variables".)  The sun functions should
              be accurate to within about 4 minutes for latitudes  lower  than
              60  degrees.   The functions are available starting from version
              03.00.07 of Remind.

       time(i_hr, i_min)
              Creates a TIME with the hour and minute components specified  by
              hr and min.

       timepart(tq_datetime)
              Returns a TIME object representing the time portion of datetime.

       today()
              Returns Remind's notion of "today."  This may be the actual sys-
              tem date, or a date supplied on the command line, or the date of
              the calendar entry currently being computed.

       trig(s_1 [,s_2, ...])
              For each string argument s_n, trig evaluates s_n as if it were a
              REM or IFTRIG trigger specification.  If the trigger would trig-
              ger today, then the trigger date  is  returned  and  no  further
              triggers  are  evaluated.  If none of the triggers would trigger
              today, then the zero date 1990-01-01 is returned.
              trig also has a zero-argument form;  this  returns  the  trigger
              date  of  the most recent trig function that returned a non-zero
              trigger date.

              trig can be used to make more sophisticated versions of  IFTRIG.
              For example, if you have meetings every Monday in June and July,
              and you want warnings 3 days in advance, you could use:

                  REM [trig("Mon Jun +3", "Mon July +3")] +3 MSG Meeting %b

              NOTE: We need to repeat the +3 delta outside of the  trig  func-
              tion for advance warning to work properly.  This is because trig
              returns a date constant (the trigger date) and the  REM  command
              does not know the details of trig's arguments.

              Note  that  because  Remind  does not have short-circuit logical
              operators, something like:

                  SET a trig("Mon +7") || trig("Fri +7")

              would set the value of trig()  to  the  date  of  the  following
              Thursday.   Even  though trig("Mon +7") always returns true, the
              logical-OR operator still evaluates trig("Fri  +7")  which  also
              returns true and sets trig().

              You  can  work  around the lack of a short-circuit logical-OR as
              follows: If trig returns a true value,  the  specific  value  it
              returns  can be coerced to a DATE which is the trigger date.  So
              the following code:

                  SET a trig("Mon +4") || trig("Fri +4")
                  IF a
                      REM [a] +4 MSG [wkday($T)] %b.
                  ENDIF

              would operate as follows:

                  On Monday:    Monday today.
                  On Tuesday:   Friday in 3 days' time.
                  On Wednesday: Friday in 2 days' time.
                  On Thursday:  Monday in 4 days' time.
                  On Friday:    Monday in 3 days' time.
                  On Saturday:  Monday in 2 days' time.
                  On Sunday:    Monday tomorrow.

              Compare with the following:

                  SET a trig("Mon +4") || trig("Fri +4")
                  IF a
                      REM [trig()] +4 MSG [wkday($T)] %b.
                  ENDIF

              which yields:

                  On Monday:    Friday in 4 days' time.
                  On Tuesday:   Friday in 3 days' time.
                  On Wednesday: Friday in 2 days' time.
                  On Thursday:  Friday tomorrow.
                  On Friday:    Friday today.
                  On Saturday:  Monday in 2 days' time.
                  On Sunday:    Monday tomorrow.

              That is because trig() returns the trigger date of the last trig
              function  that returns true, whereas the value of a is the trig-
              ger date of the first trig function that returns true.

              Important Note:  Because trig() always returns an absolute date,
              it  will not work properly with a SATISFY clause.  Consider this
              reminder:

                  REM [trig("Mar", "Apr")] SATISFY [$Td == 15] MSG 15 Mar or April

              If we run Remind on 5 March 2022, we might  expect  the  trigger
              date  to  be  calculated as 15 March 2022... but that's not what
              happens.  Instead, the trig function is evaluated first, and  it
              returns  2022-03-05.   So as far as Remind is concerned, the REM
              statement becomes:

                  REM 2022-03-05 SATISFY [$Td == 15] MSG 15 Mar or April

              and the SATISFY expression is never true.  So: Do not mix trig()
              and SATISFY.

       trigdate()
              Returns  the  calculated  trigger date of the last REM or IFTRIG
              command.  If used in the body of a  REM  command,  returns  that
              command's  trigger date.  If the most recent REM command did not
              yield a computable trigger date, returns the integer 0.

       trigdatetime()
              Similar to trigdate(), but returns a DATETIME if the most recent
              triggerable  REM  command  had an AT clause.  If there was no AT
              clause, returns a  DATE.   If  no  trigger  could  be  computed,
              returns the integer 0.  See "MULTI-DAY EVENTS" for more informa-
              tion.

       trigeventstart()
              Returns a DATETIME representing the start  of  the  most  recent
              triggerable REM command that had an AT clause.  For events with-
              out a DURATION or that do not span multiple  days,  returns  the
              same  as  trigdatetime().  If the REM command did not have an AT
              clause, returns the integer -1 (and differs from  trigdatetime()
              in  this respect.)  See "MULTI-DAY EVENTS" for more information.

       trigeventduration()
              Returns a TIME representing the  duration  of  the  most  recent
              triggerable  REM  command  that had an AT and a DURATION clause.
              If the event does not span multiple days, returns the same thing
              as  trigduration().  If the REM command lacked an AT or DURATION
              clause, returns -1.  See "MULTI-DAY EVENTS"  for  more  informa-
              tion.

       trigback()
              Returns  the  "back"  amount  of the last REM or IFTRIG command.
              Returns a positive integer N if the "back" is of the form -N, or
              a  negative  integer  if  it is of the form --N.  If there is no
              "back", then returns 0.

       trigdelta()
              Returns the "delta" amount of the last REM  or  IFTRIG  command.
              Returns  a  positive integer N if the "delta" is of the form +N,
              or a negative integer if it is of the form ++N.  If there is  no
              "delta", then returns 0.

       trigtimedelta()
              Similar  to  trigdelta(),  but  returns the delta used in the AT
              clause of a timed reminder.

       trigrep()
              Returns the "repeat" amount of the last REM or  IFTRIG  command.
              Returns  a positive integer N if the "repeat" is of the form *N.
              If there is no "repeat", then returns 0.

       trigtimerep()
              Similar to trigrep(), but returns the  repeat  used  in  the  AT
              clause of a timed reminder.

       trigduration()
              Returns  (as  a  TIME  type)  the  DURATION parameter of a timed
              reminder.  If there is no DURATION parameter, returns the  inte-
              ger -1.  See "MULTI-DAY EVENTS" for more information.

       trigpriority()
              Returns the PRIORITY of the last REM or IFTRIG command.

       triguntil()
              Returns  (as a DATE type) the UNTIL parameter of the last REM or
              IFTRIG command.  If there was no UNTIL  parameter,  returns  the
              integer  -1.   If  there  is  a  THROUGH parameter, that will be
              returned by triguntil() since  "THROUGH  yyyy-mm-dd"  is  simply
              syntactic sugar for "*1 UNTIL yyyy-mm-dd".

       trigscanfrom()
              Returns  (as a DATE type) the SCANFROM parameter of the last REM
              or IFTRIG command.  If there was no SCANFROM parameter,  returns
              the  integer  -1.   Note  that  FROM  and  SCANFROM  interact; a
              reminder that has a "FROM yyyy-mm-dd" parameter will act  as  if
              it has a SCANFROM parameter whose value is the maximum of "yyyy-
              mm-dd" and today.

       trigfrom()
              Returns (as a DATE type) the FROM parameter of the last  REM  or
              IFTRIG  command.   If  there  was no FROM parameter, returns the
              integer -1.


       trigger(d_date   [,t_time    [,i_utcflag]])    or    trigger(q_datetime
       [,i_utcflag])
              Returns a string suitable for use in a REM command or a SCANFROM
              or  UNTIL  clause,  allowing  you  to calculate trigger dates in
              advance.  Note that in earlier versions of Remind,  trigger  was
              required  to convert a date into something the REM command could
              consume.  However, in this version of Remind, you can  omit  it.
              Note  that  trigger() always returns its result in English, even
              for non-English versions of Remind.  Normally, the date and time
              are  the  local  date and time; however, if utcflag is non-zero,
              the date and time are interpreted as UTC  times,  and  are  con-
              verted to local time.  Examples:

                   trigger('1993/04/01')

              returns "1 April 1993",

                   trigger('1994/08/09', 12:33)

              returns "9 August 1994 AT 12:33", as does:

                   trigger('1994/08/09@12:33').

              Finally:

                   trigger('1994/12/01', 03:00, 1)

              returns  "30  November  1994 AT 22:00" for EST, which is 5 hours
              behind UTC.  The value for your time zone may differ.

       trigtime()
              Returns the time of the last REM command with an AT clause.   If
              the  last  REM did not have an AT clause, returns the integer 0.
              If a REM command has an AT clause with a DURATION, then you  can
              compute the end time as trigtime() + trigduration().

       trigvalid()
              Returns  1  if the value returned by trigdate() is valid for the
              most recent REM command, or 0 otherwise.  Sometimes REM commands
              cannot calculate a trigger date.  For example, the following REM
              command can never be triggered:

                 REM Mon OMIT Mon SKIP MSG Impossible!


       typeof(x_arg)
              Returns "STRING", "INT", "DATE", "TIME" or "DATETIME", depending
              on the type of arg.

       tzconvert(q_datetime, s_srczone [,s_dstzone])
              Converts  datetime  from  the  time zone named by srczone to the
              time zone named by dstzone.  If dstzone is omitted, the  default
              system time zone is used.  The return value is a DATETIME.  Time
              zone names are system-dependent; consult your  operating  system
              for legal values.  Here is an example:

           tzconvert('2007-07-08@01:14', "Canada/Eastern", "Canada/Pacific")

                 returns

           2007-07-07@22:14


       upper(s_string)
              Returns  a  STRING with all lower-case characters in string con-
              verted to upper-case.

       value(s_varname [,x_default])
              Returns the value  of  the  specified  variable.   For  example,
              value("X"+"Y")  returns  the  value  of  variable  XY,  if it is
              defined.  If XY is not defined, an error results.

              However, if you supply a second argument, it is returned if  the
              varname  is  not  defined.   The  expression value("XY", 0) will
              return 0 if XY is not defined, and the value  of  XY  if  it  is
              defined.

       version()
              Returns  a string specifying the version of Remind.  For version
              03.00.04, returns "03.00.04".  It is guaranteed that as new ver-
              sions  of  Remind  are released, the value returned by version()
              will strictly increase, according to the rules for string order-
              ing.

       weekno([dq_date, [i_wkstart, [i_daystart]]])
              Returns  the  week number of the year.  If no arguments are sup-
              plied, returns the ISO 8601 week number  for  today().   If  one
              argument date is supplied, then returns the ISO 8601 week number
              for that date.  If two arguments are supplied, then wkstart must
              range  from  0  to  6,  and represents the first day of the week
              (with 0 being Sunday and 6 being Saturday.).  If wkstart is  not
              supplied, then it defaults to 1.  If the third argument daystart
              is supplied, then it specifies when Week 1 starts.  If  daystart
              is  less  than  or  equal  to 7, then Week 1 starts on the first
              wkstart on or after January daystart.  Otherwise, Week 1  starts
              on the first wkstart on or after December daystart.  If omitted,
              daystart defaults to 29 (following the ISO 8601 definition.)

       wkday(dqi_arg)
              If arg is a DATE or DATETIME, returns a string representing  the
              day  of  the  week  of  the date.  If arg is an INT from 0 to 6,
              returns the corresponding weekday ("Sunday" to "Saturday").

       wkdaynum(dq_date)
              Returns a number from 0 to 6 representing the day-of-week of the
              specified  date.   (0 represents Sunday, and 6 represents Satur-
              day.)

       year(dq_date)
              Returns a INT that is the year component of date.



MULTI-DAY EVENTS

       If you specify a start time with AT and a duration with  DURATION,  you
       can  create  events  that  span  multiple days.  Consider these two REM
       statements:

           REM 1991-02-13 AT 16:00 DURATION 72:00 MSG 72-hour event
           REM 1991-02-13 THROUGH 1991-02-16 AT 16:00 MSG Four events

       The first statement creates a single event that starts on  13  February
       1991 at 16:00 and runs through 16 February 1991 at 16:00

       The  second statements creates four separate events that start at 16:00
       on 13, 14, 15 and 16 February 1991 and have indefinite duration.

       Remind handles multi-day events specially.  These are the rules:

       On the first day of a multi-day event, trigdatetime() will  return  the
       starting date and time of the event, and trigduration() will return the
       original DURATION.

       On each subsequent day of a multi-day event, trigdatetime() will return
       midnight  on  the  day  in question, and trigduration() will return the
       remaining duration.  Consider this example:

           #!/bin/sh
           remind - 12 feb 1991 '*6' <<'EOF'
           BANNER %
           REM 1991-02-13 AT 16:00 DURATION 72:00 SATISFY 1
           set a trigdatetime()
           set b trigduration()
           set c trigeventstart()
           set d trigeventduration()
           MSG now=[today()] dt=[a] dur=[b] estart=[c] edur=[d]%
           EOF

       The output is:

       now=1991-02-12 dt=1991-02-13@16:00 dur=72:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-13 dt=1991-02-13@16:00 dur=72:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-14 dt=1991-02-14@00:00 dur=64:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-15 dt=1991-02-15@00:00 dur=40:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-16 dt=1991-02-16@00:00 dur=16:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-17 dt=1991-02-13@16:00 dur=72:00 estart=-1 edur=-1

       As you see, the trigdatetime() and trigduration() functions return  the
       start  time and duration of the remaining portion of a multi-day event,
       whereas trigeventstart and trigeventduration always return the original
       start  and  duration of the multi-day event.  Note also that the return
       value  for  expired  reminders  is  not   reliable;   the   fact   that
       trigeventstart  and  trigeventduration  return  -1  in  that case is an
       implementation artifact.

       SELF-OVERLAPPING EVENTS

       A multi-day event has the possibility of  "overlapping  itself".   When
       this happens, Remind prefers the later event (only one copy of an event
       is ever triggered for a given date.)  Consider this example:

          #!/bin/sh
          remind - '*5' 10 Feb 1991 <<'EOF'

          BANNER %
          REM MON at 0:00 DURATION 192:0 MSG [today()] [trigeventstart()] [trigduration()]%

          EOF

       The output is:

          1991-02-10 1991-02-04@00:00 48:00
          1991-02-11 1991-02-11@00:00 192:00
          1991-02-12 1991-02-11@00:00 168:00
          1991-02-13 1991-02-11@00:00 144:00
          1991-02-14 1991-02-11@00:00 120:00

       Although  the  event  from  1991-02-04  still  has  24  hours  left  on
       1991-02-11, the fresh occurrence on 1991-02-11 takes precedences and is
       the one that is triggered.

       I do not recommend constructing self-overlapping multi-day events.



EXPRESSION PASTING

       An extremely powerful feature of Remind is  its  macro  capability,  or
       "expression pasting."

       In  almost  any  situation where Remind is not expecting an expression,
       you can "paste" an expression in.  To do this, surround the  expression
       with square brackets.  For example:

            REM [mydate] MSG foo

       This  evaluates  the  expression "mydate", where "mydate" is presumably
       some pre-computed variable, and then "pastes" the result into the  com-
       mand-line for the parser to process.

       A  formal description of this is:  When Remind encounters a "pasted-in"
       expression, it evaluates the expression, and coerces the  result  to  a
       STRING.   It  then substitutes the string for the pasted-in expression,
       and continues parsing.  Note, however, that expressions  are  evaluated
       only once, not recursively.  Thus, writing:

            ["[a+b]"]

       causes Remind to read the token "[a+b]".  It does not interpret this as
       a pasted-in expression.  In fact, the only way to get a  literal  left-
       bracket into a reminder is to use ["["].

       You  can  use expression pasting almost anywhere.  However, there are a
       few exceptions:

       o      If Remind is expecting an expression, as in the SET command,  or
              the  IF  command,  you  should not include square brackets.  For
              example, use:

                 SET a 4+5
       and not:
                 SET a [4+5]

       o      You cannot use expression pasting for the first token on a line.
              For example, the following will not work:

                 ["SET"] a 1

              This restriction is because Remind must be able to unambiguously
              determine the first token of a line for  the  flow-control  com-
              mands (to be discussed later.)

              In  fact,  if Remind cannot determine the first token on a line,
              it assumes that it is a REM command.  If  expression-pasting  is
              used,  Remind  assumes it is a REM command.  Thus, the following
              three commands are equivalent:

                        REM 12 Nov 1993 AT 13:05 MSG BOO!
                        12 Nov 1993 AT 13:05 MSG BOO!
                        [12] ["Nov " + 1993] AT [12:05+60] MSG BOO!

       o      You cannot use expression-pasting to determine  the  type  (MSG,
              CAL,  etc.)  of a REM command.  You can paste expressions before
              and after the MSG, etc. keywords, but cannot do  something  like
              this:

                 REM ["12 Nov 1993 AT 13:05 " + "MSG" + " BOO!"]

       COMMON PITFALLS IN EXPRESSION PASTING

       Remember,  when  pasting  in  expressions,  that  extra  spaces are not
       inserted.  Thus, something like:

            REM[expr]MSG[expr]

       will probably fail.

       If you use an expression to calculate a delta or back, ensure that  the
       result is a positive number.  Something like:

            REM +[mydelta] Nov 12 1993 MSG foo

       will fail if mydelta happens to be negative.



FLOW CONTROL COMMANDS

       Remind  has  commands that control the flow of a reminder script.  Nor-
       mally, reminder scripts are processed sequentially.   However,  IF  and
       related  commands  allow  you  to process files conditionally, and skip
       sections that you don't want interpreted.

       THE IF COMMAND

       The IF command has the following form:

            IF expr
                 t-command
                 t-command...
            ELSE
                 f-command
                 f-command...
            ENDIF

       Note that the commands are shown indented for clarity.  Also, the  ELSE
       portion can be omitted.  IF commands can be nested up to a small limit,
       probably around 8 or 16 levels of nesting, depending on your system.

       If the expr evaluates to a non-zero INT, a DATE that is not 1990-01-01,
       a TIME that is not 00:00, a DATETIME that is not 1990-01-01@00:00, or a
       non-null STRING, then the IF portion is considered true, and the t-com-
       mands are executed.  If expr evaluates to zero or null, then the f-com-
       mands (if the ELSE portion is present) are executed.

       Examples:

            IF defined("want_hols")
                 INCLUDE /usr/share/remind/holidays
            ENDIF

            IF today() > '1992/2/10'
                 set missed_ap "You missed it!"
            ELSE
                 set missed_ap "Still have time..."
            ENDIF

       THE IFTRIG COMMAND

       The IFTRIG command is similar to an IF command, except that it computes
       a  trigger  (as  in the REM command), and evaluates to true if a corre-
       sponding REM command would trigger.  Examples:

            IFTRIG 1 Nov
                 ; Executed on 1 Nov
            ELSE
                 ; Executed except on 1 Nov
            ENDIF

            IFTRIG 1 -1 OMIT Sat Sun +4
                 ; Executed on last working day of month,
                 ; and the 4 working days preceding it
            ELSE
                 ; Executed except on above days
            ENDIF

       Note that the IFTRIG command computes a  trigger  date,  which  can  be
       retrieved  with the trigdate() function.  You can use all of the normal
       trigger components, such as UNTIL, delta, etc. in the  IFTRIG  command.
       However,  you  cannot use a type specifier such as CAL, MSG or SATISFY;
       attempting to do so yields a parse error.



USER-DEFINED FUNCTIONS

       In addition to the built-in functions, Remind allows you to define your
       own functions.  The FSET command does this for you:

       FSET fname(args) expr

       Fname  is the name of the function, and follows the convention for nam-
       ing variables.  Args is a comma-separated list of arguments,  and  expr
       is  an expression.  Args can be empty, in which case you define a func-
       tion taking no parameters.  Here are some examples:

            FSET double(x) 2*x
            FSET yeardiff(date1, date2) year(date1) - year(date2)
            FSET since(x) ord(year(trigdate())-x)

       The last function is useful in birthday reminders.  For example:

            REM 1 Nov +12 MSG Dean's [since(1984)] birthday is %b.

       Dean was born in 1984.  The above example, on 1  November  1992,  would
       print:

            Dean's 8th birthday is today.

       Notes:

       o      If  you  access  a  variable  in expr that is not in the list of
              arguments, the "global" value (if any) is used.

       o      Function and parameter names are significant only to 12  charac-
              ters.

       o      The  value()  function  always  accesses the "global" value of a
              variable, even if it has the same  name  as  an  argument.   For
              example:

                        fset func(x) value("x")
                        set x 1
                        set y func(5)

              The  above sequence sets y to 1, which is the global value of x.

       o      User-defined functions may call other functions, including other
              user-defined   functions.   However,  recursive  calls  are  not
              allowed.

       o      User-defined functions are  not  syntax-checked  when  they  are
              defined; parsing occurs only when they are called.

       o      If a user-defined function has the same name as a built-in func-
              tion, it is ignored and the built-in function is used.  To  pre-
              vent  conflicts with future versions of Remind (which may define
              more built-in functions), you may wish to name all  user-defined
              functions beginning with an underscore.



PRECISE SCHEDULING

       The  WARN keyword allows precise control over advance warning in a more
       flexible manner than the delta mechanism.  It should be followed by the
       name of a user-defined function, warn_function.

       If  a warn_function is supplied, then it must take one argument of type
       INT.  Remind ignores any delta, and instead calls warn_function succes-
       sively with the arguments 1, 2, 3, ...

       Warn_function's return value n is interpreted as follows:

       o      If  n is positive, then the reminder is triggered exactly n days
              before its trigger date.

       o      If n is negative, then it is triggered n days before its trigger
              date, not counting OMITted days.

       As  an  example, suppose you wish to be warned of American Independence
       Day 5, 3, and 1 days in advance.  You could use this:

            FSET _wfun(x) choose(x, 5, 3, 1, 0)
            REM 4 July WARN _wfun MSG American Independence Day is %b.

       NOTES

       1      If an error occurs during the evaluation of warn_function,  then
              Remind  stops  calling  it and simply issues the reminder on its
              trigger date.

       2      If the absolute-values of the return values of warn_function are
              not monotonically decreasing, Remind stops calling it and issues
              the reminder on its trigger date.

       3      Warn_function should (as a matter of good style) return 0 as the
              final  value  in  its  sequence  of  return  values.  However, a
              reminder will always be triggered on its trigger  date,  regard-
              less of what warn_function does.

       Similarly  to  WARN,  the SCHED keyword allows precise control over the
       scheduling of timed reminders.  It should be followed by the name of  a
       user-defined function, sched_function.

       If a scheduling function is supplied, then it must take one argument of
       type INT.  Rather than using the AT time, time delta, and time  repeat,
       Remind  calls  the scheduling function to determine when to trigger the
       reminder.  The first time the reminder is queued, the scheduling  func-
       tion  is called with an argument of 1.  Each time the reminder is trig-
       gered, it is re-scheduled by calling the scheduling function again.  On
       each call, the argument is incremented by one.

       The  return  value of the scheduling function must be an INT or a TIME.
       If the return value is a TIME, then the reminder is re-queued to  trig-
       ger  at that time.  If it is a positive integer n, then the reminder is
       re-queued to trigger at the  previous  trigger  time  plus  n  minutes.
       Finally,  if it is a negative integer or zero, then the reminder is re-
       queued to trigger n minutes before the AT time.  Note that  there  must
       be an AT clause for the SCHED clause to do anything.

       Here's an example:

            FSET _sfun(x) choose(x, -60, 30, 15, 10, 3, 1, 1, 1, 1, 0)
            REM AT 13:00 SCHED _sfun MSG foo

       The reminder would first be triggered at 13:00-60 minutes, or at 12:00.
       It would next be triggered 30 minutes later, at 12:30.  Then, it  would
       be triggered at 12:45, 12:55, 12:58, 12:59, 13:00, 13:01 and 13:02.

       NOTES

       1      If  an  error  occurs  during the evaluation of sched_func, then
              Remind reverts to using the AT time and  the  delta  and  repeat
              values, and never calls sched_func again.

       2      If  processing sched_func yields a time earlier than the current
              system time, it is repeatedly called  with  increasing  argument
              until  it  yields  a  value greater than or equal to the current
              time.  However, if the sequence of values calculated during  the
              repetition  is  not  strictly increasing, then Remind reverts to
              the default behaviour and never calls sched_func again.

       3      It is quite possible  using  sched_func  to  keep  triggering  a
              reminder even after the AT-time.  However, it is not possible to
              reschedule a reminder past midnight - no crossing of date bound-
              aries  is  allowed.  Also, it is quite possible to not trigger a
              reminder on the AT time when  you  use  a  scheduling  function.
              However,  if your scheduling function is terminated (for reasons
              1 and 2) before the AT time of the reminder, it  will  be  trig-
              gered at the AT time, because normal processing takes over.

       4      Your  scheduling  functions  should  (as a matter of good style)
              return 0 when no more scheduling is required.  See the  example.

       5      All  scheduling  functions are evaluated after the entire Remind
              script has been read in.  So whatever function  definitions  are
              in effect at the end of the script are used.



THE SATISFY CLAUSE

       The form of REM that uses SATISFY is as follows:

       REM trigger SATISFY expr

       The  way  this  works is as follows:  Remind first calculates a trigger
       date, in the normal fashion.  Next, it sets trigdate()  to  the  calcu-
       lated  trigger date.  It then evaluates expr.  If the result is not the
       null string or zero, processing ends.  Otherwise, Remind  computes  the
       next  trigger  date, and re-tests expr.  This iteration continues until
       expr evaluates to non-zero or non-null, or until  the  iteration  limit
       specified with the -x command-line option is reached.

       If  expr  is  not satisfied, then trigvalid() is set to 0 and the error
       message "Can't compute trigger" is issued.  Otherwise,  trigvalid()  is
       set to 1.

       This is really useful only if expr involves a call to the trigdate() or
       related functions; otherwise, expr will not change as Remind  iterates.

       An example of the usefulness of SATISFY:  Suppose you wish to be warned
       of every Friday the 13th.  Your first attempt may be:

            # WRONG!
            REM Fri 13 +2 MSG Friday the 13th is %b.

       But this won't work.  This reminder triggers on the first Friday on  or
       after  the 13th of each month.  The way to do it is with a more compli-
       cated sequence:

            REM 13 SATISFY wkdaynum(trigdate()) == 5
            IF trigvalid()
                 REM [trigdate()] +2 MSG \
                 Friday the 13th is %b.
            ENDIF

       You can write the REM statement a little more concisely:

            REM 13 SATISFY $Tw == 5

       Let's see how this works.  The SATISFY clause iterates through all  the
       13ths of successive months, until a trigger date is found whose day-of-
       week is Friday (== 5).  If a valid date was found, we  use  the  calcu-
       lated trigger date to set up the next reminder.

       We could also have written:

            REM Fri SATISFY day(trigdate()) == 13

       but  this  would  result in more iterations, since "Fridays" occur more
       often than "13ths of the month."

       Here is another example: Suppose you want to be reminded  of  something
       on  the 15th of January, April, July, and October.  You could make four
       separate reminders, or you could use:

               REM 15 SATISFY [isany($Tm, 1, 4, 7, 10)] MSG 15th Reminder!

       This technique of using one REM command to calculate a trigger date  to
       be used by another command is quite powerful.  For example, suppose you
       wanted to OMIT Labour day, which is the first Monday in September.  You
       could use:

            # Note: SATISFY 1 is an idiom for "do nothing"
            REM Mon 1 Sept SATISFY 1
            OMIT [trigdate()]

       CAVEAT: This only omits the next Labour Day, not all Labour Days in the
       future.  This could cause strange results,  as  the  OMIT  context  can
       change depending on the current date.  For example, if you use the fol-
       lowing command after the above commands:

            REM Mon AFTER msg hello

       the result will not be as you expect.  Consider  producing  a  calendar
       for  September,  1992.   Labour  Day  was on Monday, 7 September, 1992.
       However, when Remind gets around to calculating the trigger  for  Tues-
       day,  8  September,  1992, the OMIT command will now be omitting Labour
       Day for 1993, and the "Mon AFTER" command will not be triggered.   (But
       see  the  description of SCANFROM in the section "DETAILS ABOUT TRIGGER
       COMPUTATION.")

       It is probably best to stay away  from  computing  OMIT  trigger  dates
       unless you keep these pitfalls in mind.

       For  versions  of Remind starting from 03.00.07, you can include a MSG,
       RUN, etc. clause in a SATISFY clause as follows:

            REM trigger_stuff SATISFY [expr] MSG body

       Note that for this case only, the expr after SATISFY must  be  enclosed
       in square brackets.  It must come after all the other components of the
       trigger, and immediately before the MSG, RUN, etc.  keyword.   If  expr
       cannot be satisfied, then the reminder is not triggered.

       Thus, the "Friday the 13th" example can be expressed more compactly as:

            REM 13 +2 SATISFY [$Tw == 5] MSG Friday the 13th is %b.

       And you can trigger a reminder on  Mondays,  Wednesdays  and  Thursdays
       occurring on odd-numbered days of the month with the following:

            REM Mon Wed Thu SATISFY [$Td %2 ] MSG Here it is!!!

       Note  that  SATISFY  and  OMITFUNC  can often be used to solve the same
       problem, though in different ways.  Sometimes a SATISFY is cleaner  and
       sometimes an OMITFUNC; experiment and use whichever seems clearer.



POSSIBLY-UNCOMPUTABLE TRIGGERS

       Occasionally,  you  may  wish  to  suppress the "Can't compute trigger"
       warnings for reminders for which a trigger  date  cannot  be  computed.
       For  example,  the  following reminder is triggered on a Monday that is
       not a holiday if the following Tuesday is a holiday:

               REM Mon SKIP SATISFY [isomitted($T+1)] MSG Work between holidays

       However, if there are no Mondays after today's date  that  satisfy  the
       condition,  Remind  will  print  the "Can't compute trigger" error.  To
       suppress this, use the MAYBE-UNCOMPUTABLE keyword:

               REM MAYBE-UNCOMPUTABLE Mon SKIP SATISFY [isomitted($T+1)] MSG Work between holidays

       It's almost never appropriate to use MAYBE-UNCOMPUTABLE, but it is pro-
       vided  for those rare occasions when it makes sense.  If you use MAYBE-
       UNCOMPUTABLE inside the evaltrig() function, then  untriggerable  trig-
       gers return -1.  For example:

               SET a evaltrig("MAYBE-UNCOMPUTABLE Mon SKIP OMIT Mon")

       will set a to -1.


DEBUGGING REMINDER SCRIPTS

       Although  the  command-line  -d  option  is useful for debugging, it is
       often overkill.  For example, if you turn  on  the  -dx  option  for  a
       reminder  file  with many complex expressions, you'll get a huge amount
       of output.  The DEBUG command allows you to control the debugging flags
       under program control.  The format is:

       DEBUG [+flagson] [-flagsoff]

       Flagson and flagsoff consist of strings of the characters "extvlf" that
       correspond to the  debugging  options  discussed  in  the  command-line
       options  section.   If  preceded with a "+", the corresponding group of
       debugging options is switched on.  Otherwise, they  are  switched  off.
       For example, you could use this sequence to debug a complicated expres-
       sion:

            DEBUG +x
            set a very_complex_expression(many_args)
            DEBUG -x

       THE DUMPVARS COMMAND

       The command DUMPVARS displays the values of variables in  memory.   Its
       format is:

       DUMPVARS [var...]

       If you supply a space-separated list of variable names, the correspond-
       ing variables are displayed.  If you do not supply a list of variables,
       then all variables in memory are displayed.  To dump a system variable,
       put its name in the list of variables to dump.  If you put a lone  dol-
       lar  sign  in  the list of variables to dump, then all system variables
       will be dumped.

       THE ERRMSG COMMAND

       The ERRMSG command has the following format:

       ERRMSG body

       The body is passed through the substitution filter  (with  an  implicit
       trigger date of today()) and printed to the error output stream.  Exam-
       ple:

            IF !defined("critical_var")
                 ERRMSG You must supply a value for "critical_var"
                 EXIT
            ENDIF

       THE EXIT COMMAND

       The above example also shows the use of the EXIT command.  This  causes
       an  unconditional  exit  from  script  processing.   Any  queued  timed
       reminders are discarded.  If you are in calendar mode (described next),
       then the calendar processing is aborted.

       If  you  supply  an  INT-type  expression after the EXIT command, it is
       returned to the calling program as the exit status.  Otherwise, an exit
       status of 99 is returned.

       THE FLUSH COMMAND

       This  command  simply  consists  of the word FLUSH on a line by itself.
       The command flushes the standard output and standard error streams used
       by Remind.  This is not terribly useful to most people, but may be use-
       ful if you run Remind as a subprocess of another program, and  want  to
       use pipes for communication.



CALENDAR MODE

       If you supply the -c, -s or -p command-line option, then Remind runs in
       "calendar mode."  In this mode, Remind interprets  the  script  repeat-
       edly,  performing  one iteration through the whole file for each day in
       the calendar.  Reminders that trigger are saved  in  internal  buffers,
       and then inserted into the calendar in the appropriate places.

       If  you  also  supply the -a option, then Remind will not include timed
       reminders in the calendar.

       The -p option is used in conjunction with the Rem2PS program to produce
       a  calendar  in  PostScript format.  For example, the following command
       will send PostScript code to standard output:

            remind -p .reminders | rem2ps

       You can print a PostScript calendar by piping this to the lpr  command.

       If you have a reminder script called ".reminders", and you execute this
       command:

            remind -c .reminders jan 1993

       then Remind executes the script 31 times, once for each day in January.
       Each  time  it executes the script, it increments the value of today().
       Any reminders whose trigger date matches today() are entered  into  the
       calendar.

       MSG and CAL-type reminders, by default, have their entire body inserted
       into the calendar.  RUN-type reminders are not normally  inserted  into
       the  calendar.   However,  if  you enclose a portion of the body in the
       %"...%" sequence, only that portion is inserted.  For example, consider
       the following:

            REM 6 Jan MSG %"Dianne's birthday%" is %b

       In  the normal mode, Remind would print "Dianne's birthday is today" on
       6 January.  However, in the calendar  mode,  only  the  text  "Dianne's
       birthday" is inserted into the box for 6 January.

       If you explicitly use the %"...%" sequence in a RUN-type reminder, then
       the text between the delimiters is inserted into the calendar.  If  you
       use  the  sequence %"%" in a MSG or CAL-type reminder, then no calendar
       entry is produced for that reminder.

       PRESERVING VARIABLES

       Because Remind iterates through the script for each day in  the  calen-
       dar,  slow operations may severely reduce the speed of producing a cal-
       endar.

       For example, suppose you set the variables "me" and "hostname" as  fol-
       lows:

            SET me shell("whoami")
            SET hostname shell("hostname")

       Normally,  Remind  clears  all variables between iterations in calendar
       mode.  However, if certain variables are slow to compute, and will  not
       change  between  iterations,  you  can "preserve" their values with the
       PRESERVE command.   Also,  since  function  definitions  are  preserved
       between  calendar iterations, there is no need to redefine them on each
       iteration.  Thus, you could use the following sequence:

            IF ! defined("initialized")
                 set initialized 1
                 set me shell("whoami")
                 set hostname shell("hostname")
                 fset func(x) complex_expr
                 preserve initialized me hostname
            ENDIF

       The operation is as  follows:   On  the  first  iteration  through  the
       script,  "initialized"  is  not defined.  Thus, the commands between IF
       and ENDIF are executed.  The PRESERVE command ensures that  the  values
       of  initialized,  me  and  hostname are preserved for subsequent itera-
       tions.  On the next iteration, the commands are skipped, since initial-
       ized has remained defined.  Thus, time-consuming operations that do not
       depend on the value of today() are done only once.

       Most system variables (those whose names start with '$') are  automati-
       cally preserved between calendar iterations.

       Note  that  for  efficiency, Remind caches the reminder script (and any
       INCLUDEd files) in memory when producing a calendar.

       Timed reminders are sorted and placed into the calendar in time  order.
       These are followed by non-timed reminders.  Remind automatically places
       the time of timed reminders in the calendar according to  the  -b  com-
       mand-line  option.   Reminders in calendar mode are sorted as if the -g
       option had been used; you can change the sort order in calendar mode by
       explicitly  using  the  -g option to specify a different order from the
       default.

       REPEATED EXECUTION

       If you supply a repeat parameter on the command line, and  do  not  use
       the  -c, -p, or -s options, Remind operates in a similar manner to cal-
       endar mode.  It repeatedly executes the reminder  script,  incrementing
       today() with each iteration.  The same rules about preserving variables
       and function definitions apply.  Note that using repeat on the  command
       line  also  enables  the  -q  option and disables any -z option.  As an
       example, if you want to see how Remind will behave for the  next  week,
       you can type:

            remind .reminders '*7'

       If you want to print the dates of the next 1000 days, use:

            (echo 'banner %'; echo 'msg [today()]%') | remind - '*1000'



INITIALIZING VARIABLES ON THE COMMAND LINE

       The  -i  option  is  used to initialize variables on the Remind command
       line.  The format is -ivar=expr, where expr is  any  valid  expression.
       Note  that  you  may have to use quotes or escapes to prevent the shell
       from interpreting special characters in expr.  You can have as many  -i
       options  as  you  want  on  the command line, and they are processed in
       order.  Thus, if a variable is defined in one  -i  option,  it  can  be
       referred to by subsequent -i options.

       Note  that  if  you supply a date on the command line, it is not parsed
       until all options have been processed.  Thus, if you use today() in any
       of the -i expressions, it will return the same value as realtoday() and
       not the date supplied on the command line.

       Any variables defined on the command line are  preserved  as  with  the
       PRESERVE command.

       You  should  not  have  any  spaces between the -i option and the equal
       sign; otherwise, strange variable names are created that  can  only  be
       accessed with the value() or defined() functions.

       You can also define a function on the command line by using:

       -ifunc(args)=definition

       Be sure to protect special characters from shell interpretation.


MORE ABOUT POSTSCRIPT

       The  PS  and  PSFILE  reminders  pass  PostScript  code directly to the
       printer.  They differ in that the  PS-type  reminder  passes  its  body
       directly to the PostScript output (after processing by the substitution
       filter) while the PSFILE-type's body should simply consist of  a  file-
       name.   The  Rem2PS program will open the file named in the PSFILE-type
       reminder, and include its contents in the PostScript output.

       The PostScript-type reminders for a particular day are included in  the
       PostScript  output in sorted order of priority.  Note that the order of
       PostScript commands has a major impact on the appearance of the  calen-
       dars.  For example, PostScript code to shade a calendar box will oblit-
       erate code to draw a moon symbol if the moon symbol code is  placed  in
       the  calendar  first.   For  this  reason, you should not provide PS or
       PSFILE-type reminders with priorities; instead, you should ensure  that
       they  appear  in  the reminder script in the correct order.  PostScript
       code should draw objects working from the background to the foreground,
       so  that  foreground  objects properly overlay background ones.  If you
       prioritize these reminders and run the  script  using  descending  sort
       order for priorities, the PostScript output will not work.

       All of the PostScript code for a particular date is enclosed in a save-
       restore pair.  However, if several PostScript-type reminders are  trig-
       gered for a single day, each section of PostScript is not enclosed in a
       save-restore pair - instead, the entire body of included PostScript  is
       enclosed.

       PostScript-type reminders are executed by the PostScript printer before
       any regular calendar entries.   Thus,  regular  calendar  entries  will
       overlay the PostScript-type reminders, allowing you to create shaded or
       graphical backgrounds for particular days.

       Before executing your PostScript code, the  origin  of  the  PostScript
       coordinate  system  is positioned to the bottom left-hand corner of the
       "box" in the calendar representing today().  This location  is  exactly
       in  the  middle  of the intersection of the bottom and left black lines
       delineating the box - you may have to  account  for  the  thickness  of
       these lines when calculating positions.

       Several  PostScript  variables are available to the PostScript code you
       supply.  All distance and size variables are in PostScript units  (1/72
       inch.)  The variables are:

       LineWidth
              The width of the black grid lines making up the calendar.

       Border The  border  between  the center of the grid lines and the space
              used to print calendar entries.  This border is  normally  blank
              space.

       BoxWidth and BoxHeight
              The  width and height of the calendar box, from center-to-center
              of the black gridlines.

       InBoxHeight
              The height from the center of the bottom black gridline  to  the
              top  of the regular calendar entry area.  The space from here to
              the top of the box is used only to draw the day number.

       /DayFont, /EntryFont, /SmallFont, /TitleFont and /HeadFont
              The fonts used to draw the day numbers,  the  calendar  entries,
              the  small  calendars,  the calendar title (month, year) and the
              day-of-the-week headings, respectively.

       DaySize, EntrySize, TitleSize and HeadSize
              The sizes of the above fonts.  (The size of the  small  calendar
              font  is not defined here.)  For example, if you wanted to print
              the Hebrew date next to the regular day number in the  calendar,
              use:

            REM PS Border BoxHeight Border sub DaySize sub moveto \
               /DayFont findfont DaySize scalefont setfont \
               ([hebday(today())] [hebmon(today())]) show

              Note how /DayFont and DaySize are used.

       Note  that  if  you  supply  PostScript code, it is possible to produce
       invalid PostScript files.  Always test your PostScript thoroughly  with
       a  PostScript  viewer before sending it to the printer.  You should not
       use any document structuring comments in your PostScript code.



DAEMON MODE

       If you use the -z command-line option,  Remind  runs  in  the  "daemon"
       mode.   In  this mode, no "normal" reminders are issued.  Instead, only
       timed reminders are collected and queued, and are then issued  whenever
       they reach their trigger time.

       In  addition,  Remind wakes up every few minutes to check the modifica-
       tion date on the reminder script (the filename supplied on the  command
       line.)   If  Remind detects that the script has changed, it re-executes
       itself in daemon mode, and interprets the changed script.

       In daemon mode, Remind also re-reads the remind script when it  detects
       that the system date has changed.

       In  daemon  mode,  Remind acts as if the -f option had been used, so to
       run in the daemon mode in the background, use:

            remind -z .reminders &

       If you use sh or bash, you may have  to  use  the  "nohup"  command  to
       ensure that the daemon is not killed when you log out.




PURGE MODE

       If  you  supply  the -j command-line option, Remind runs in purge mode.
       In this mode, it tries to purge expired reminders  from  your  reminder
       files.

       In  purge  mode, Remind reads your reminder file and creates a new file
       by appending ".purged" to the original file  name.   Note  that  Remind
       never edits your original file; it always creates a new .purged file.

       If  you  invoke  Remind  against  a directory instead of a file, then a
       .purged file is created for each *.rem file in the directory.

       Normally, Remind does not create  .purged  files  for  INCLUDed  files.
       However,  if  you  supply a numeric argument after -j, then Remind will
       create .purged files for the specified level of INCLUDE.  For  example,
       if  you invoke Remind with the argument -j2, then .purged files will be
       created for the file (or directory) specified on the command line,  any
       files  included  by  them, and any files included by those files.  How-
       ever, .purged files will  not  be  created  for  third-or-higher  level
       INCLUDE files.

       Determining  which  reminders have expired is extremely tricky.  Remind
       does its best, but you should always compare the .purged  file  to  the
       original file and hand-merge the changes back in.

       Remind annotates the .purged file as follows:

       An expired reminder is prefixed with:  #!P: Expired:

       In situations where Remind cannot reliably determine that something was
       expired, you may see the following comments inserted before  the  prob-
       lematic line:

          #!P: Cannot purge SATISFY-type reminders

          #!P: The next IF evaluated false...
          #!P: REM statements in IF block not checked for purging.

          #!P: The previous IF evaluated true.
          #!P: REM statements in ELSE block not checked for purging

          #!P: The next IFTRIG did not trigger.
          #!P: REM statements in IFTRIG block not checked for purging.

          #!P: Next line has expired, but contains expression...  please verify

          #!P: Next line may have expired, but contains non-constant expression

          #!P! Could not parse next line: Some-Error-Message-Here

       Remind  always annotates .purged files with lines beginning with "#!P".
       If such lines are encountered in the original file, they are not copied
       to the .purged file.




SORTING REMINDERS

       The -g option causes Remind to sort reminders by trigger date, time and
       priority before issuing them.  Note that reminders are still calculated
       in  the  order  encountered  in the script.  However, rather than being
       issued immediately, they are saved in an internal buffer.  When  Remind
       has  finished  processing  the script, it issues the saved reminders in
       sorted order.  The -g option can be followed by up to  four  characters
       that  must  all  be "a" or "d".  The first character specifies the sort
       order by trigger date (ascending or descending), the  second  specifies
       the  sort  order by trigger time and the third specifies the sort order
       by priority.  If the fourth character is "d", the untimed reminders are
       sorted  before  timed  reminders.  The default is to sort all fields in
       ascending order and to sort untimed reminders after timed reminders.

       In ascending order, reminders are issued with the most imminent  first.
       Descending  order is the reverse.  Reminders are always sorted by trig-
       ger date, and reminders with the same trigger date are then  sorted  by
       trigger  time.   If two reminders have the same date and time, then the
       priority is used to break ties.  Reminders with the same date, time and
       priority are issued in the order they were encountered.

       You can define a user-defined function called SORTBANNER that takes one
       DATE-type argument.  In sort mode, the following sequence happens:

       If Remind notices that the next reminder to issue has a different trig-
       ger  date  from  the  previous  one  (or  if  it is the first one to be
       issued), then SORTBANNER is called with the trigger date as  its  argu-
       ment.   The  result is coerced to a string, and passed through the sub-
       stitution filter with the appropriate trigger date.  The result is then
       displayed.

       Here's an example - consider the following fragment:

            # Switch off the normal banner
            BANNER %
            REM 11 March 1993 ++1 MSG Not so important
            REM 17 March 1993 ++7 MSG Way in the future
            REM 10 March 1993 MSG Important Reminder
            REM 11 March 1993 ++1 MSG Not so important - B
            FSET sortbanner(x) iif(x == today(), \
                 "***** THINGS TO DO TODAY *****", \
                 "----- Things to do %b -----")

       Running this with the -gaa option on 10 March 1993 produces the follow-
       ing output:

            ***** THINGS TO DO TODAY *****

            Important Reminder

            ----- Things to do tomorrow -----

            Not so important

            Not so important - B

            ----- Things to do in 7 days' time -----

            Way in the future

       You can use the args() built-in function to determine  whether  or  not
       SORTBANNER has been defined.  (This could be used, for example, to pro-
       vide a default definition for SORTBANNER in a system-wide file included
       at the end of the user's file.)  Here's an example:

            # Create a default sortbanner function if it hasn't already
            # been defined
            if args("sortbanner") != 1
                 fset sortbanner(x) "--- Things to do %b ---"
            endif



MSGPREFIX() AND MSGSUFFIX()

       You can define two functions in your script called msgprefix() and msg-
       suffix().  They should each accept one argument, a  number  from  0  to
       9999.

       In normal mode, for MSG- and MSF-type reminders, the following sequence
       occurs when Remind triggers a reminder:

       o      If msgprefix() is defined, it is evaluated with the priority  of
              the reminder as its argument.  The result is printed.  It is not
              passed through the substitution filter.

       o      The body of the reminder is printed.

       o      If msgsuffix() is defined, it is evaluated with the priority  of
              the reminder as its argument.  The result is printed.  It is not
              passed through the substitution filter.

       Here's  an  example:   The  following  definition   causes   priority-0
       reminders to be preceded by "URGENT", and priority-6000 reminders to be
       preceded by "(not important)".

            fset msgprefix(x) iif(x==0, "URGENT: ", \
                 x==6000, "(not important) ", "")

       In Calendar Mode (with the -c, -s or -p options), an analogous pair  of
       functions  named calprefix() and calsuffix() can be defined.  They work
       with all reminders that produce an entry in the  calendar  (i.e.,  CAL-
       and possibly RUN-type reminders as well as MSG-type reminders.)

       NOTES

       Normally,  the  body  of  a  reminder is followed by a carriage return.
       Thus, the results of msgsuffix() will appear on the next line.  If  you
       don't  want  this, end the body of the reminder with a percentage sign,
       "%".  If you want a space between your reminders, simply include a car-
       riage return (char(13)) as part of the msgsuffix() return value.

       If  Remind has problems evaluating msgprefix(), msgsuffix() or sortban-
       ner(), you will see a lot of error messages.  For an example  of  this,
       define the following:

            fset msgprefix(x) x/0



COMPILE-TIME SUPPORT FOR OTHER LANGUAGES

       Your  version  of  Remind  may have been compiled to support a language
       other than English.  This support may or may  not  be  complete  -  for
       example,  all  error  and usage messages may still be in English.  How-
       ever, at a minimum, non-English versions of Remind will output names of
       months  and  weekdays in the selected language.  Also, the substitution
       mechanism will substitute constructs suitable for the selected language
       rather than for English.

       Note  that  a  non-English  version  of Remind will accept only English
       names of weekdays and months in a reminder script.



RUN-TIME SUPPORT FOR OTHER LANGUAGES

       Remind has run-time support for other languages,  and  it  is  expected
       that compile-time support will be deprecated in favour of run-time sup-
       port.

       A number of system variables let you translate various phrases to other
       languages.  These system variables are:


       $Monday, $Tuesday, $Wednesday, $Thursday, $Friday, $Saturday
              Set  each of these system variables to a string representing the
              corresponding day's name in  your  language.   Strings  must  be
              valid UTF-8 strings.

       $January,  $February,  $March,  $April,  $May,  $June,  $July, $August,
       $September, $October, $November, $December
              Set  each of these system variables to a string representing the
              corresponding month's name in your language.   Strings  must  be
              valid UTF-8 strings.

       $Ago, $Am, $And, $At, $Hour, $Is, $Minute, $Now, $On, $Pm, $Was
              Set  each  of  these  system variables to the translation of the
              corresponding English word into your language.   Note  that  $Am
              and $Pm should be the translations of "AM" and "PM" (morning and
              afternoon time indicators) respectively.

       $Hplu, $Mplu
              Set these to the suffix to  add  to  the  word  for  "hour"  and
              "minute"  to make them plural.  In English, both would be set to
              "s".

       $Fromnow
              Set this to the translation of the English phrase "from now"

       Note that if you set any of the language-related system variables, they
       should be set in a section of your script that always is evaluated.  If
       you set them inside an IF statement, for example,  results  are  unpre-
       dictable.

       Note  also  that the Rem2PS back-end does not support the full range of
       UTF-8 characters.  The TkRemind, rem2html and rem2pdf back-ends all  do
       support the full UTF-8 range.



RUN-TIME MODIFICATION OF THE SUBSTITUTION FILTER

       The  system  variables  mentioned in the previous section are not typi-
       cally sufficient to properly translate Remind's output to another  lan-
       guage.   Some  languages  have complicated rules for AM vs PM times and
       others have complex rules for making words  plural.   Remind  therefore
       allows  you to define a number of functions that modify the behavior of
       the substitution filter at run-time.  The functions are:


       subst_ampm(h)
              This function is passed a single integer, namely an hour from  0
              to 23.  It should return a string that indicates "AM" or "PM" or
              even finer gradations in some languages.

       subst_ordinal(d)
              This function is passed a single integer, namely a  day  of  the
              month  from 1 to 31.  It should return a string that is suffixed
              to the day number  to  turn  it  into  an  ordinal  number.   In
              English, for example, the function might return "st", "nd", "rd"
              or "th", depending on d.

       subst_N(alt, date, time)
              This is actually a family of functions, where N is a  letter  or
              number.   This  function  completely  overrides the substitution
              sequence "%X".  The three arguments are an integer alt which, if
              non-zero,   indicates   that   the  alternate-mode  substitution
              sequence "%*X" was encountered; date which is the  trigger  date
              of the reminder and time which is the trigger time.

       subst_Nx(alt, date, time)
              Again,  this  is  a  family  of functions.  It is similar to the
              subst_N family except it is only called if date is two  or  more
              days  away  from  today().   This is useful if you don't want to
              override the "today" or "tomorrow" output for most  substitution
              sequences.

       Here's  an example of how you might customize your substitution filter.
       Suppose you want to change the "%b" sequence  to  substitute  "the  day
       after tomorrow" for an event two days from now.  You could do this:

           FSET subst_bx(a,d,t) iif(d==today()+2, "the day after tomorrow",                              "in " + (d-today()) + " days' time")
           REM [today()+3] ++3 MSG Event 1 is %b%
           REM [today()+2] ++3 MSG Event 2 is %b%
           REM [today()+1] ++3 MSG Event 3 is %b%
           REM [today()]   ++3 MSG Event 4 is %b%

       The output of this script is:

           Event 1 is in 3 days' time
           Event 2 is the day after tomorrow
           Event 3 is tomorrow
           Event 4 is today

       Note  how  Event  2's  wording  was changed from the normal "in 2 days'
       time", and note also that the "tomorrow" and "today"  events  used  the
       normal  substitution---subst_bx is not called for trigger days of today
       or tomorrow.

       As a special case, if a subst_Nx or subst_N function returns the  inte-
       ger  zero,  then the normal substitution mechanism is used.  Therefore,
       the previous example could have been written more simply as:

           FSET subst_bx(a,d,t) iif(d==today()+2, "the day after tomorrow", 0)



LANGUAGE PACKS

       Remind ships with a number of language packs, which are simply reminder
       scripts located in [$SysInclude]/lang.  The currently-shipping language
       packs are:

       da.rem (Danish), de.rem (German), es.rem  (Spanish),  fr.rem  (French),
       is.rem  (Icelandic),  it.rem  (Italian), nl.rem (Dutch), no.rem (Norwe-
       gian), pl.rem (Polish), pt.rem (Portuguese) and ro.rem (Romanian).

       To use a language pack (in this example, de.rem), simply place this  at
       the top of your reminders file:

           INCLUDE [$SysInclude]/lang/de.rem

       If  you  want  Remind  to try to find the language pack appropriate for
       your locale settings, use:

           INCLUDE [$SysInclude]/lang/auto.rem

       You are encouraged to study the language packs to see how to  translate
       Remind into additional languages.



THE HEBREW CALENDAR

       Remind  has support for the Hebrew calendar, which is a luni-solar cal-
       endar.  This allows  you  to  create  reminders  for  Jewish  holidays,
       jahrzeits (anniversaries of deaths) and smachot (joyous occasions.)

       THE HEBREW YEAR

       The  Hebrew  year  has 12 months, alternately 30 and 29 days long.  The
       months are: Tishrey, Heshvan, Kislev, Tevet, Shvat, Adar, Nisan,  Iyar,
       Sivan,  Tamuz,  Av  and  Elul.   In Biblical times, the year started in
       Nisan, but Rosh Hashana (Jewish New Year) is now celebrated on the  1st
       and 2nd of Tishrey.

       In  a  cycle  of 19 years, there are 7 leap years, being years 3, 6, 8,
       11, 14, 17 and 19 of the cycle.  In a leap year, an extra month  of  30
       days is added before Adar.  The two Adars are called Adar A and Adar B.

       For certain religious reasons, the  year  cannot  start  on  a  Sunday,
       Wednesday  or Friday.  To adjust for this, a day is taken off Kislev or
       added to Heshvan.  Thus, a regular year can have from 353 to 355  days,
       and a leap year from 383 to 385.

       When Kislev or Heshvan is short, it is called chaser, or lacking.  When
       it is long, it is called shalem, or full.

       The Jewish date changes at sunset.  However,  Remind  will  change  the
       date at midnight, not sunset.  So in the period between sunset and mid-
       night, Remind will be a day earlier than the true  Jewish  date.   This
       should not be much of a problem in practice.

       The  computations  for  the  Jewish  calendar were based on the program
       "hdate" written by Amos Shapir of the Hebrew University  of  Jerusalem,
       Israel.  He also supplied the preceding explanation of the calendar.

       HEBREW DATE FUNCTIONS

       hebday(d_date)
              Returns  the  day  of the Hebrew month corresponding to the date
              parameter.  For example, 12 April 1993 corresponds to  21  Nisan
              5753.  Thus, hebday('1993/04/12') returns 21.

       hebmon(d_date)
              Returns the name of the Hebrew month corresponding to date.  For
              example, hebmon('1993/04/12') returns "Nisan".

       hebyear(d_date)
              Returns the Hebrew year corresponding  to  date.   For  example,
              hebyear('1993/04/12') returns 5753.

       hebdate(i_day, s_hebmon [,id_yrstart [,i_jahr [,i_aflag]]])
              The hebdate() function is the most complex of the Hebrew support
              functions.  It can take from 2 to 5  arguments.   It  returns  a
              DATE corresponding to the Hebrew date.

              The  day parameter can range from 1 to 30, and specifies the day
              of the Hebrew month.  The hebmon parameter is a string that must
              name  one  of  the Hebrew months specified above.  Note that the
              month must be spelled out in full, and use the English translit-
              eration  shown  previously.   You  can also specify "Adar A" and
              "Adar B."  Month names are not case-sensitive.

              The yrstart parameter can either be a DATE or an INT.  If it  is
              a DATE, then the hebdate() scans for the first Hebrew date on or
              after that date.  For example:

                        hebdate(15, "Nisan", '1990/01/01')

              returns 1990/03/30, because that is the first occurrence  of  15
              Nisan on or after 1 January 1990.

              If yrstart is an INT, it is interpreted as a Hebrew year.  Thus:

                        hebdate(22, "Kislev", 5756)

              returns 1995/12/15, because that date corresponds to 22  Kislev,
              5756.   Note  that  none  of the Hebrew date functions will work
              with dates outside Remind's normal range for dates.

              If yrstart is not supplied, it defaults to today().

              The jahr modifies the behaviour of hebdate() as follows:

              If jahr is 0 (the default), then hebdate() keeps scanning  until
              it  finds  a  date  that exactly satisfies the other parameters.
              For example:

                        hebdate(30, "Adar A", 1993/01/01)

              returns 1995/03/02, corresponding to 30 Adar  A,  5755,  because
              that  is the next occurrence of 30 Adar A after 1 January, 1993.
              This behaviour  is  appropriate  for  Purim  Katan,  which  only
              appears in leap years.

              If jahr is 1, then the date is modified as follows:

              o      30 Heshvan is converted to 1 Kislev in years when Heshvan
                     is chaser

              o      30 Kislev is converted to 1 Tevet in years when Kislev is
                     chaser

              o      30 Adar A is converted to 1 Nisan in non-leapyears

              o      Other  dates in Adar A are moved to the corresponding day
                     in Adar in non-leapyears

              This behaviour is appropriate for smachot (joyous occasions) and
              for some jahrzeits - see "JAHRZEITS."

              if jahr is 2, then the date is modified as follows:

              o      30  Kislev  and 30 Heshvan are converted to 29 Kislev and
                     29 Heshvan, respectively, if the month is chaser

              o      30 Adar A is converted to 30 Shvat in non-leapyears

              o      Other dates in Adar A are moved to the corresponding  day
                     in Adar in non-leapyears

              if  jahr  is not 0, 1, or 2, it is interpreted as a Hebrew year,
              and the behaviour is calculated as described in  the  next  sec-
              tion, "JAHRZEITS."

              The  aflag  parameter modifies the behaviour of the function for
              dates in Adar during leap years.  The  aflag  is  only  used  if
              yrstart is a DATE type.

              The  aflag only affects date calculations if hebmon is specified
              as "Adar".  In leap years, the following algorithm is followed:

              o      If aflag is 0, then the date  is  triggered  in  Adar  B.
                     This is the default.

              o      If  aflag  is  1,  then  the date is triggered in Adar A.
                     This may be appropriate for jahrzeits  in  the  Ashkenazi
                     tradition; consult a rabbi.

              o      If  aflag is 2, then the date is triggered in both Adar A
                     and Adar B of  a  leap  year.   Some  Ashkenazim  perform
                     jahrzeit in both Adar A and Adar B.

       JAHRZEITS

       A  jahrzeit  is a yearly commemoration of someone's death.  It normally
       takes place on the anniversary of the death,  but  may  be  delayed  if
       burial is delayed - consult a rabbi for more information.

       In addition, because some months change length, it is not obvious which
       day the anniversary of a death is.  The following rules are used:

       o      If the death occurred on 30 Heshvan, and  Heshvan  in  the  year
              after  the  death is chaser, then the jahrzeit is observed on 29
              Heshvan  in  years  when  Heshvan  is  chaser.   Otherwise,  the
              yahrzeit is observed on 1 Kislev when Heshvan is chaser.

       o      If the death occurred on 30 Kislev, and Kislev in the year after
              the death is chaser, then the jahrzeit is observed on 29  Kislev
              in  years  when  Kislev  is  chaser.  Otherwise, the yahrzeit is
              observed on 1 Tevet when Kislev is chaser.

       o      If the death occurred on 1-29 Adar A, it  is  observed  on  1-29
              Adar in non-leapyears.

       o      If  the  death occurred on 30 Adar A, it is observed on 30 Shvat
              in a non-leapyear.

       Specifying a Hebrew year for the jahr parameter causes the correct  be-
       haviour  to be selected for a death in that year.  You may also have to
       specify aflag, depending on your tradition.

       The jahrzeit information was supplied by Frank Yellin, who quoted  "The
       Comprehensive Hebrew Calendar" by Arthur Spier, and "Calendrical Calcu-
       lations" by E. M. Reingold and Nachum Dershowitz.



OUT-OF-BAND REMINDERS

       The SPECIAL keyword is used to transmit  "out-of-band"  information  to
       Remind  backends,  such as tkremind or Rem2PS.  They are used only when
       piping data from a remind -p line.  (Note that the COLOR special is  an
       exception;  it  downgrades  to the equivalent of MSG in remind's normal
       mode of operation.)

       The various SPECIALs recognized are particular for each  backend;  how-
       ever,  there are four SPECIALs that all backends should attempt to sup-
       port.  They are currently supported by Rem2PS, tkremind and rem2html.

       The SHADE special replaces the psshade() function.  Use it like this:

            REM Sat Sun SPECIAL SHADE 128
            REM Mon SPECIAL SHADE 255 0 0

       The SHADE keyword is followed by either one or three numbers, from 0 to
       255.   If  one  number  is  supplied, it is interpreted as a grey-scale
       value from black (0) to white (255).  If three  numbers  are  supplied,
       they  are  interpreted  as  RGB  components from minimum (0) to maximum
       (255).  The example above shades weekends a fairly dark grey and  makes
       Mondays  a  fully-saturated  red.   (These shadings appear in calendars
       produced by Rem2PS, tkremind and rem2html.)

       The MOON special replaces the psmoon() function.  Use it like this:

            REM [moondate(0)] SPECIAL MOON 0
            REM [moondate(1)] SPECIAL MOON 1
            REM [moondate(2)] SPECIAL MOON 2
            REM [moondate(3)] SPECIAL MOON 3

       These draw little moons on the various calendars.  The complete  syntax
       of the MOON special is as follows:

            ... SPECIAL MOON phase moonsize fontsize msg

       Phase  is  a  number from 0 to 3, with 0 representing a new moon, 1 the
       first quarter, 2 a full moon and 3 the last quarter.

       moonsize is the diameter in PostScript units of the moon to  draw.   If
       omitted or supplied as -1, the backend chooses an appropriate size.

       fontsize is the font size in PostScript units of the msg

       Msg is additional text that is placed near the moon glyph.

       Note  that  only the Rem2PS backend supports moonsize and fontsize; the
       other backends use fixed sizes.

       The COLOR special lets you place colored  reminders  in  the  calendar.
       Use it like this:

            REM ... SPECIAL COLOR 255 0 0 This is a bright red reminder
            REM ... SPECIAL COLOR 0 128 0 This is a dark green reminder

       You  can  spell  COLOR either the American way ("COLOR") or the British
       way ("COLOUR").  This manual will use the American way.

       Immediately following COLOR should be  three  decimal  numbers  ranging
       from 0 to 255 specifying red, green and blue intensities, respectively.
       The rest of the line is the text to put in the calendar.

       The COLOR special is "doubly special", because in its normal  operating
       mode,  remind  treats  a  COLOR  special just like a MSG-type reminder.
       Also, if you invoke Remind with -@[n],  then  it  approximates  SPECIAL
       COLOR reminders on your terminal.

       See  also the documentation of the $DefaultColor system variable in the
       section "SYSTEM VARIABLES".

       The WEEK special lets you place annotations such as the week number  in
       the  calendar.  For example, this would number each Monday with the ISO
       8601 week number.  The week number is shown like this: "(Wn)"  in  this
       example, but you can put whatever text you like after the WEEK keyword.

            REM Monday SPECIAL WEEK (W[weekno()])



MISCELLANEOUS

       COMMAND ABBREVIATIONS

       The following tokens can be abbreviated:

       o      REM can be omitted - it is implied if no other valid command  is
              present.

       o      CLEAR-OMIT-CONTEXT --> CLEAR

       o      PUSH-OMIT-CONTEXT --> PUSH

       o      POP-OMIT-CONTEXT --> POP

       o      DUMPVARS --> DUMP

       o      BANNER --> BAN

       o      INCLUDE --> INC

       o      SCANFROM --> SCAN

       NIFTY EXAMPLES

       This section is a sampling of what you can do with Remind.

            REM 5 Feb 1991 AT 14:00 +45 *30 \
            RUN mail -s "Meeting at %2" $LOGNAME </dev/null &

       On  5 February, 1991, this reminder will mail you reminders of a 2:00pm
       meeting at 1:15, 1:45 and 2:00.  The subject of the mail  message  will
       be "Meeting at 2:00pm" and the body of the message will be blank.

            REM AT 17:00 RUN echo "5:00pm - GO HOME!" | xless -g +0+0 &

       This  reminder  will  pop  up an xless window at 5:00pm every day.  The
       xless window will contain the line "5:00pm - GO HOME!"

            REM AT 23:59 RUN (sleep 120; remind -a [filename()]) &

       This reminder will run at one minute to midnight.  It will cause a  new
       Remind  process  to start at one minute past midnight.  This allows you
       to have a continuous reminder service so you can work through the night
       and still get timed reminders for early in the morning.  Note that this
       trick is no longer necessary, providing you run Remind in daemon  mode.

            remind -c12 /dev/null Jan 1993

       This  invocation  of Remind will cause it to print a calendar for 1993,
       with all entries left blank.

            REM CAL [trigdate()-date(year(trigdate()), 1, 1)+1]

       This example puts an entry in each box of a calendar showing the number
       (1-365 or 366) of the day of the year.

            REM Tue 2 Nov SATISFY (year(trigdate())%4) == 0
            IF trigvalid()
                 REM [trigdate()] ++5 MSG \
                 U.S. Presidential Election!!
            ENDIF

       This example warns you 5 days ahead of each American presidential elec-
       tion.  The first REM command calculates the  first  Tuesday  after  the
       first  Monday in November.  (This is equivalent to the first Tuesday on
       or after 2 November.)  The SATISFY clause ensures that the trigger date
       is issued only in election years, which are multiples of 4.  The second
       REM command actually issues the reminder.

       DETAILS ABOUT TRIGGER COMPUTATION

       Here is a conceptual description of how triggers are calculated.   Note
       that  Remind  actually  uses  a  much more efficient procedure, but the
       results are the same as if the conceptual procedure had been  followed.

       Remind starts from the current date (that is, the value of today()) and
       scans forward, examining each day one at a time until it finds  a  date
       that  satisfies  the  trigger,  or  can prove that no such dates (on or
       later than today()) exist.

       If Remind is  executing  a  SATISFY-type  reminder,  it  evaluates  the
       expression with trigdate() set to the date found above.  If the expres-
       sion evaluates to zero or the null string, Remind continues  the  scan-
       ning procedure described above, starting with the day after the trigger
       found above.

       The SCANFROM clause (having a syntax similar to UNTIL) can  modify  the
       search  strategy used.  In this case, Remind begins the scanning proce-
       dure at scan_date, which is the date specified in the SCANFROM  clause.
       For example:

            REM Mon 1 SCANFROM 17 Jan 1992 MSG Foo

       The example above will always have a trigger date of Monday, 3 February
       1992.  That is because Remind starts scanning from 17 January 1992, and
       stops scanning as soon as it hits a date that satisfies "Mon 1."

       The  main  use of SCANFROM is in situations where you want to calculate
       the positions of floating holidays.  Consider the  Labour  Day  example
       shown  much  earlier.  Labour Day is the first Monday in September.  It
       can move over a range of 7 days.  Consider the following sequence:

            REM Mon 1 Sept SCANFROM [today()-7] ADDOMIT MSG Labour Day
            REM Mon AFTER MSG Hello

       The SCANFROM clause makes sure that Remind begins scanning from 7  days
       before  the current date.  This ensures that Labour Day for the current
       year will continue to be triggered until 7 days after it has  occurred.
       This allows you to safely use the AFTER keyword as shown.

       As a special case, you can simply use a negative number after SCANFROM;
       a negative number -N is interpreted as N days before today.  Thus,  the
       previous example could also be written like this:

            REM Mon 1 Sept SCANFROM -7 ADDOMIT MSG Labour Day
            REM Mon AFTER MSG Hello

       In  general,  use SCANFROM as shown for safe movable OMITs.  The amount
       you should scan back by (7 days in the example above)  depends  on  the
       number  of possible consecutive OMITted days that may occur, and on the
       range of the movable holiday.  Generally, a value of 7 is safe.

       The FROM clause operates almost like the  counterpoint  to  UNTIL.   It
       prevents  the reminder from triggering before the FROM date.  For exam-
       ple, the following reminder:

            REM Mon Thu FROM 23 Jul 2007 UNTIL 2 Aug 2007 MSG Test

       will trigger on Mondays and Thursdays between 23 July 2007 and 2 August
       2007 inclusive.

       FROM  is  really just syntactic sugar; you could implement the reminder
       above as follows:

            REM Mon Thu SCANFROM [max(today(), '2007-07-23')] \
                   UNTIL 2 Aug 2007 MSG Test

       but that's a lot  harder  to  read.   Internally,  Remind  treats  FROM
       exactly as illustrated using SCANFROM.  For that reason, you cannot use
       both FROM and SCANFROM.

       Note that if you use one REM command to calculate a trigger date,  per-
       form  date calculations (addition or subtraction, for example) and then
       use the modified date in a subsequent REM command, the results may  not
       be what you intended.  This is because you have circumvented the normal
       scanning mechanism.  You should try to write REM commands that  compute
       trigger  dates  that can be used unmodified in subsequent REM commands.
       The file "defs.rem" that comes with the  Remind  distribution  contains
       examples.

       DETAILS ABOUT TRIGVALID()

       The  trigvalid() function returns 1 if Remind could find a trigger date
       for the previous REM or IFTRIG command.  More specifically, it  returns
       1  if  Remind finds a date not before the starting date of the scanning
       that satisfies the trigger.  In addition, there is one special case  in
       which trigvalid() returns 1 and trigdate() returns a meaningful result:

       If the REM or IFTRIG command did not contain an UNTIL clause, and  con-
       tained all of the day, month and year components, then Remind will cor-
       rectly compute a trigger date, even if it  happens  to  be  before  the
       start  of  scanning.  Note that this behaviour is not true for versions
       of Remind prior to 03.00.01.


AUTHOR

       Dianne Skoll <dianne@skoll.ca> wrote Remind.  The moon code was  copied
       largely  unmodified  from  "moontool"  by John Walker.  The sunrise and
       sunset functions use ideas from programs by Michael Schwartz  and  Marc
       T. Kaufman.  The Hebrew calendar support was taken from "hdate" by Amos
       Shapir.  OS/2 support was done by Darrel Hankerson,  Russ  Herman,  and
       Norman Walsh.  The supported languages and their translators are listed
       below.  Languages marked "complete" support error  messages  and  usage
       instructions in that language; all others only support the substitution
       filter mechanism and month/day names.

       German -- Wolfgang Thronicke

       Dutch -- Willem Kasdorp and Erik-Jan Vens

       Finnish -- Mikko Silvonen (complete)

       French -- Laurent Duperval (complete)

       Norwegian -- Trygve Randen

       Danish -- Mogens Lynnerup

       Polish -- Jerzy Sobczyk (complete)

       Brazilian Portuguese -- Marco Paganini (complete)

       Italian -- Valerio Aimale

       Romanian -- Liviu Daia

       Spanish -- Rafa Couto

       Icelandic -- Bjorn Daviosson


BUGS

       There's no good reason why read-only system variables  are  not  imple-
       mented  as  functions,  or  why functions like version(), etc.  are not
       implemented as read-only system variables.

       Hebrew dates in Remind change at midnight instead of sunset.

       Remind has some built-in limits (for example, number of global  OMITs.)



BIBLIOGRAPHY

       Nachum  Dershowitz  and Edward M. Reingold, "Calendrical Calculations",
       Software-Practice and Experience, Vol. 20(9), Sept. 1990, pp 899-928.

       L. E. Doggett, Almanac  for  computers  for  the  year  1978,  Nautical
       Almanac Office, USNO.

       Richard Siegel and Michael and Sharon Strassfeld, The First Jewish Cat-
       alog, Jewish Publication Society of America.



SEE ALSO

       remind(1), rem2html(1)




4th Berkeley Distribution        14 March 2022                       remind(1)

remind 04.00.00 - Generated Sun May 15 05:49:56 CDT 2022
© manpagez.com 2000-2025
Individual documents may contain additional copyright information.