UPDWTMP(3)

UPDWTMP(3)                 Linux Programmer's Manual                UPDWTMP(3)

NAME
       updwtmp, logwtmp - append an entry to the wtmp file

SYNOPSIS
       #include <utmp.h>

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

       For logwtmp(), link with -lutil.

DESCRIPTION
       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
       /var/log/wtmp
              database of past user logins

ATTRIBUTES
       For  an  explanation  of  the  terms  used  in  this  section,  see at-
       tributes(7).

       +-----------+---------------+--------------------------+
       |Interface  | Attribute     | Value                    |
       +-----------+---------------+--------------------------+
       |updwtmp(), | Thread safety | MT-Unsafe sig:ALRM timer |
       |logwtmp()  |               |                          |
       +-----------+---------------+--------------------------+

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

NOTES
       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.

SEE ALSO
       getutxent(3), wtmp(5)

COLOPHON
       This page is part of release 5.07 of the Linux  man-pages  project.   A
       description  of  the project, information about reporting bugs, and the
       latest    version    of    this    page,    can     be     found     at
       https://www.kernel.org/doc/man-pages/.

GNU                               2017-09-15                        UPDWTMP(3)