updwtmp(3) - Linux manual page (original) (raw)

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 ***_wtmpfile_**, 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

   _/var/log/wtmp_
          database of past user logins

ATTRIBUTES top

   For an explanation of the terms used in this section, see
   [attributes(7)](../man7/attributes.7.html).
   ┌─────────────────────┬───────────────┬──────────────────────────┐
   │ **Interface** │ **Attribute** │ **Value** │
   ├─────────────────────┼───────────────┼──────────────────────────┤
   │ **updwtmp**(),          │ Thread safety │ MT-Unsafe sig:ALRM timer │
   │ **logwtmp**()           │               │                          │
   └─────────────────────┴───────────────┴──────────────────────────┘

VERSIONS top

   For consistency with the other "utmpx" functions (see
   [getutxent(3)](../man3/getutxent.3.html)), glibc provides (since glibc 2.1):

       **#define _GNU_SOURCE** /* See feature_test_macros(7) */
       **#include <utmpx.h>**
       **void updwtmpx (const char ***_wtmpxfile_**, 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

   None.

HISTORY top

   Solaris, NetBSD.

SEE ALSO top

   [getutxent(3)](../man3/getutxent.3.html), [wtmp(5)](../man5/wtmp.5.html)

COLOPHON top

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Linux man-pages 6.10 2024-07-23 updwtmp(3)

Pages that refer to this page:utmp(5)