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gawk: PC Using

 
 B.3.1.3 Using 'gawk' on PC Operating Systems
 ............................................
 
 Under MS-Windows, the Cygwin and MinGW environments support both the
 '|&' operator and TCP/IP networking (⇒TCP/IP Networking).
 
    The MS-Windows version of 'gawk' searches for program files as
 described in ⇒AWKPATH Variable.  However, semicolons (rather than
 colons) separate elements in the 'AWKPATH' variable.  If 'AWKPATH' is
 not set or is empty, then the default search path is
 '.;c:/lib/awk;c:/gnu/lib/awk'.
 
    Under MS-Windows, 'gawk' (and many other text programs) silently
 translates end-of-line '\r\n' to '\n' on input and '\n' to '\r\n' on
 output.  A special 'BINMODE' variable (c.e.)  allows control over these
 translations and is interpreted as follows:
 
    * If 'BINMODE' is '"r"' or one, then binary mode is set on read
      (i.e., no translations on reads).
 
    * If 'BINMODE' is '"w"' or two, then binary mode is set on write
      (i.e., no translations on writes).
 
    * If 'BINMODE' is '"rw"' or '"wr"' or three, binary mode is set for
      both read and write.
 
    * 'BINMODE=NON-NULL-STRING' is the same as 'BINMODE=3' (i.e., no
      translations on reads or writes).  However, 'gawk' issues a warning
      message if the string is not one of '"rw"' or '"wr"'.
 
 The modes for standard input and standard output are set one time only
 (after the command line is read, but before processing any of the 'awk'
 program).  Setting 'BINMODE' for standard input or standard output is
 accomplished by using an appropriate '-v BINMODE=N' option on the
 command line.  'BINMODE' is set at the time a file or pipe is opened and
 cannot be changed midstream.
 
    The name 'BINMODE' was chosen to match 'mawk' (⇒Other
 Versions).  'mawk' and 'gawk' handle 'BINMODE' similarly; however,
 'mawk' adds a '-W BINMODE=N' option and an environment variable that can
 set 'BINMODE', 'RS', and 'ORS'.  The files 'binmode[1-3].awk' (under
 'gnu/lib/awk' in some of the prepared binary distributions) have been
 chosen to match 'mawk''s '-W BINMODE=N' option.  These can be changed or
 discarded; in particular, the setting of 'RS' giving the fewest
 "surprises" is open to debate.  'mawk' uses 'RS = "\r\n"' if binary mode
 is set on read, which is appropriate for files with the MS-DOS-style
 end-of-line.
 
    To illustrate, the following examples set binary mode on writes for
 standard output and other files, and set 'ORS' as the "usual"
 MS-DOS-style end-of-line:
 
      gawk -v BINMODE=2 -v ORS="\r\n" ...
 
 or:
 
      gawk -v BINMODE=w -f binmode2.awk ...
 
 These give the same result as the '-W BINMODE=2' option in 'mawk'.  The
 following changes the record separator to '"\r\n"' and sets binary mode
 on reads, but does not affect the mode on standard input:
 
      gawk -v RS="\r\n" -e "BEGIN { BINMODE = 1 }" ...
 
 or:
 
      gawk -f binmode1.awk ...
 
 With proper quoting, in the first example the setting of 'RS' can be
 moved into the 'BEGIN' rule.
 
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