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NAME | SYNOPSIS | DESCRIPTION | FILES | ATTRIBUTES | CONFORMING TO | NOTES | SEE ALSO | COLOPHON |
UPDWTMP(3) Linux Programmer's Manual UPDWTMP(3)
updwtmp, logwtmp - append an entry to the wtmp file
#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.
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.
/var/log/wtmp
database of past user logins
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() │ │ │
└───────────┴───────────────┴──────────────────────────┘
Not in POSIX.1. Present on Solaris, NetBSD, and perhaps other
systems.
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.
getutxent(3), wtmp(5)
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latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
GNU 2015-04-19 UPDWTMP(3)
Pages that refer to this page: utmp(5)