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).

       +-----------+---------------+--------------------------+
       |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 4.15 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)