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endutxent(3)             BSD Library Functions Manual             endutxent(3)


NAME

     endutxent, getutxent, getutxid, getutxline, pututxline, setutxent -- user
     accounting database functions


LIBRARY

     Standard C Library (libc, -lc)


SYNOPSIS

     #include <utmpx.h>

     void
     endutxent(void);

     struct utmpx *
     getutxent(void);

     struct utmpx *
     getutxid(const struct utmpx *id);

     struct utmpx *
     getutxline(const struct utmpx *line);

     struct utmpx *
     pututxline(const struct utmpx *utx);

     void
     setutxent(void);


DESCRIPTION

     These functions provide access to the utmpx(5) user accounting database.

     getutxent() reads the next entry from the database; if the database was
     not yet open, it also opens it.  setutxent() resets the database, so that
     the next getutxent() call will get the first entry.  endutxent() closes
     the database.

     getutxid() returns the next entry of the type specified in its argument's
     ut_type field, or NULL if none is found.  getutxline() returns the next
     LOGIN_PROCESS or USER_PROCESS entry which has the same name as specified
     in the ut_line field, or NULL if no match is found.

     pututxline() adds the argument utmpx(5) entry line to the accounting
     database, replacing a previous entry for the same user if it exists.
     Only the superuser may write to the accounting database.

   The utmpx structure
     The utmpx structure has the following definition:

     struct utmpx {
             char ut_user[_UTX_USERSIZE];    /* login name */
             char ut_id[_UTX_IDSIZE];        /* id */
             char ut_line[_UTX_LINESIZE];    /* tty name */
             pid_t ut_pid;                   /* process id creating the entry */
             short ut_type;                  /* type of this entry */
             struct timeval ut_tv;           /* time entry was created */
             char ut_host[_UTX_HOSTSIZE];    /* host name */
             __uint32_t ut_pad[16];          /* reserved for future use */
     };

     Valid entries for ut_type are:
           BOOT_TIME        Time of a system boot.
           DEAD_PROCESS     A session leader exited.
           EMPTY            No valid user accounting information.
           INIT_PROCESS     A process spawned by init(8).
           LOGIN_PROCESS    The session leader of a logged-in user.
           NEW_TIME         Time after system clock change.
           OLD_TIME         Time before system clock change.
           RUN_LVL          Run level.  Provided for compatibility, not used.
           USER_PROCESS     A user process.
           SHUTDOWN_TIME    Time of system shutdown (extension to the stan-
                            dards).

     For each value of ut_type, the other fields with meaningful values are as
     follows:
           BOOT_TIME        ut_tv
           DEAD_PROCESS     ut_id, ut_pid, ut_tv
           EMPTY            (no others)
           INIT_PROCESS     ut_id, ut_pid, ut_tv
           LOGIN_PROCESS    ut_id, ut_user (implementation-defined name of the
                            login process), ut_pid, ut_tv
           NEW_TIME         ut_tv
           OLD_TIME         ut_tv
           RUN_LVL          (no used)
           USER_PROCESS     ut_id, ut_user (login name of the user), ut_line,
                            ut_pid, ut_host (hostname of remote user) ut_tv
           SHUTDOWN_TIME    ut_tv

   Other extensions to the standards
     The ut_type value may also be OR-ed with the following masks:
           UTMPX_AUTOFILL_MASK
                 Depending on the main part of ut_type value, other fields are
                 automatically filled in (as specified in the meaningful
                 fields table above).  In particular, the ut_id field will be
                 set using the convention of the last four characters of the
                 ut_line field (itself filled in automatically from the tty
                 name of the device connected to the standard input, output or
                 error, whichever is available).  Note that it is more effi-
                 cient to fill in as many values as are already available
                 beforehand, rather than have then automatically filled in.
           UTMPX_DEAD_IF_CORRESPONDING_MASK
                 When ut_type value is DEAD_PROCESS, a call to pututxline()
                 will succeed only if a corresponding entry already exists
                 with a ut_type value of USER_PROCESS.

     Note that the above mask values do not show up in any file format, or in
     any subsequent reads of the data.

     To support wtmpx and lastlogx equivalent capability, pututxline() auto-
     matically writes to the appropriate files.  Additional APIs to read these
     files is available in endutxent_wtmp(3) and getlastlogx(3).

   Backward compatibility
     Successful calls to pututxline() will automatically write equivalent
     entries into the utmp, wtmp and lastlog files.  Programs that read these
     old files should work as expected.  However, directly writing to these
     files does not make corresponding entries in utmpx and the wtmpx and
     lastlogx equivalent files, so such write-access is deprecated.


RETURN VALUES

     getutxent() returns the next entry, or NULL on failure (end of database
     or problems reading from the database).  getutxid() and getutxline()
     return the matching structure on success, or NULL if no match was found.

     pututxline() returns the structure that was successfully written, or NULL
     is returned and the global variable errno is set to indicate the error.


ERRORS

     No errors are defined for the endutxent(), getutxent(), getutxid(),
     getutxline(), and setutxent() functions.

     The pututxline() function may fail if:

     [EPERM]            The process does not have appropriate privileges.

     [EINVAL]           The UTMPX_DEAD_IF_CORRESPONDING_MASK flags was speci-
                        fied along with DEAD_PROCESS, but no corresponding
                        entry with USER_PROCESS was found.

     Other errors may be returned if UTMPX_AUTOFILL_MASK was specified, and a
     field could not be auto-filled.


SEE ALSO

     endutxent_wtmp(3), getlastlogx(3), utmpx(5)


STANDARDS

     The endutxent(), getutxent(), getutxid(), getutxline(), pututxline(),
     setutxent() all conform to IEEE Std 1003.1-2001 (``POSIX.1'') (XSI exten-
     sion), and previously to X/Open Portability Guide Issue 4, Version 2
     (``XPG4.2'').  The fields ut_user, ut_id, ut_line, ut_pid, ut_type, and
     ut_tv conform to IEEE Std 1003.1-2001 (``POSIX.1'') (XSI extension), and
     previously to X/Open Portability Guide Issue 4, Version 2 (``XPG4.2'').

BSD                              June 29, 2006                             BSD

Mac OS X 10.8 - Generated Mon Aug 27 16:21:06 CDT 2012
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