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.
DESCRIPTIONupdwtmp() 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 ALSOgetutxent(3), wtmp(5)COLOPHON
This page is part of release 4.14 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)
