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(), 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
Colophon
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Referenced By
The man pages logwtmp(3) and updwtmpx(3) are aliases of updwtmp(3).