daemon(3) [redhat man page]

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)

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

NAME

       daemon - run in the background

SYNOPSIS

       #include <unistd.h>

       int daemon(int nochdir, int noclose);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       daemon(): _BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)

DESCRIPTION

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

       If nochdir is zero, daemon() changes the calling process's current working directory to the root directory ("/");  otherwise,  the  current
       working directory is left unchanged.

       If  noclose  is zero, daemon() redirects standard input, standard output and standard error to /dev/null; otherwise, no changes are made to
       these file descriptors.

RETURN VALUE

       (This function forks, and if the fork(2) succeeds, the parent calls _exit(2), so that further errors are seen by the child only.)  On  suc-
       cess daemon() returns zero.  If an error occurs, daemon() returns -1 and sets errno to any of the errors specified for the fork(2) and set-
       sid(2).

CONFORMING TO

       Not in POSIX.1-2001.  A similar function appears on the BSDs.  The daemon() function first appeared in 4.4BSD.

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.

SEE ALSO

       fork(2), setsid(2)

COLOPHON

       This  page is part of release 3.53 of the Linux man-pages project.  A description of the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.

GNU
								    2009-12-05								 DAEMON(3)