redhat man page for daemon

DAEMON(3)						     Linux Programmer's Manual							 DAEMON(3)

NAME
       daemon - run in the background

SYNOPSIS
       #include <unistd.h>

       int daemon(int nochdir, int noclose);

DESCRIPTION
       The  daemon()  function is for programs wishing to detach themselves from the controlling terminal and run in the background as system dae-
       mons.

       Unless the argument nochdir is non-zero, daemon() changes the current working directory to the root ("/").

       Unless the argument noclose is non-zero, daemon() will redirect standard input, standard output and standard error to /dev/null.

RETURN VALUE
       (This function forks, and if the fork() succeeds, the father does _exit(0), so that further errors are seen by the child only.)	On success
       zero  will  be returned.  If an error occurs, daemon() returns -1 and sets the global variable errno to any of the errors specified for the
       library functions fork(2) and setsid(2).

SEE ALSO
       fork(2), setsid(2)

NOTES
       The glibc implementation can also return -1 when /dev/null exists but is not a character device with the expected major and minor  numbers.
       In this case errno need not be set.

HISTORY
       The daemon() function first appeared in BSD4.4.

BSD MANPAGE
							    1993-06-09								 DAEMON(3)