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 (), logwtmp () |
Thread safety |
MT-Unsafe sig:ALRM timer |
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)