updwtmp(3) — Linux manual page


updwtmp(3)              Library Functions Manual              updwtmp(3)

NAME         top

       updwtmp, logwtmp - append an entry to the wtmp file

LIBRARY         top

       System utilities library (libutil, -lutil)

SYNOPSIS         top

       #include <utmp.h>

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

DESCRIPTION         top

       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.

FILES         top

              database of past user logins

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       │ Interface          Attribute     Value                    │
       │ updwtmp(),         │ Thread safety │ MT-Unsafe sig:ALRM timer │
       │ logwtmp()          │               │                          │

VERSIONS         top

       For consistency with the other "utmpx" functions (see
       getutxent(3)), glibc provides (since glibc 2.1):

           #define _GNU_SOURCE          /* See feature_test_macros(7) */
           #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.

STANDARDS         top


HISTORY         top

       Solaris, NetBSD.

SEE ALSO         top

       getutxent(3), wtmp(5)

COLOPHON         top

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Linux man-pages 6.9.1          2024-05-02                     updwtmp(3)

Pages that refer to this page: utmp(5)