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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
     attributes(7).

     allbox; lb lb lbw24 l l l.  Interface Attribute Value T{ updwtmp(),
     logwtmp() T}   Thread safety  MT-Unsafe sig:ALRM timer

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 4.16 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)