Manpages - updwtmp.3

updwtmp, logwtmp - append an entry to the wtmp file

  #include <utmp.h>

  void updwtmp(const char *wtmp_file, const struct utmp *ut);
  void logwtmp(const char *line, const char *name",constchar*"host);

For *logwtmp*(), link with -lutil.

*updwtmp*() appends the utmp structure ut to the wtmp file.

*logwtmp*() constructs a utmp structure using line, name, host, current time, and current process ID. Then it calls *updwtmp*() to append the structure to the wtmp file.

/var/log/wtmp

database of past user logins

For an explanation of the terms used in this section, see *attributes*(7).

Not in POSIX.1. Present on Solaris, NetBSD, and perhaps other systems.

For consistency with the other “utmpx” functions (see *getutxent*(3)), glibc provides (since version 2.1):

  #include <utmpx.h>
  void updwtmpx (const char *wtmpx_file, const struct utmpx *utx);

This function performs the same task as *updwtmp*(), but differs in that it takes a utmpx structure as its last argument.

*getutxent*(3), *wtmp*(5)

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