NAME
pidfile —
write a daemon pid file
SYNOPSIS
#include
<util.h>
int
pidfile(const
char *basename);
DESCRIPTION
pidfile()
writes a file containing the process ID of the program to the
/var/run directory. The file name has the form
/var/run/basename.pid. If the
basename argument is NULL,
pidfile will determine the program name and use that
instead.
The pid file can be used as a quick reference if the process needs to be sent a signal. When the program exits, the pid file will be removed automatically, unless the program receives a fatal signal.
RETURN VALUES
pidfile() returns 0 on success and -1 on
failure.
SEE ALSO
HISTORY
The pidfile function call appeared in
OpenBSD 3.0.
CAVEATS
If pidfile() is called multiple times with
different basename, only the last pidfile will be
removed upon exit.
pidfile() uses
atexit() to ensure the pidfile is unlinked at
program exit. However, programs that use the _exit()
function (for example, in signal handlers) will not trigger this
behaviour.