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
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).

Interface Attribute Value
updwtmp(), logwtmp() 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 5.11 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/.


  Copyright 1997 Nicolás Lichtmaier <nickdebian.org>
Created Wed Jul  2 23:27:34 ART 1997

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Added info on availability, aeb, 971207
Added -lutil remark, 030718
2008-07-02, mtk, document updwtmpx()