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.\"	@(#)daemon.3	8.1 (Berkeley) 6/9/93
.\"
.Dd September 3, 1999
.Dt DAEMON 3
.Os
.Sh NAME
.Nm daemon
.Nd run in the background
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.Fd #include <stdlib.h>
.Ft int
.Fn daemon "int nochdir" "int noclose"
.Sh DESCRIPTION
The
.Fn daemon
function is for programs wishing to detach themselves from the
controlling terminal and run in the background as system daemons.
.Pp
Unless the argument
.Fa nochdir
is non-zero,
.Fn daemon
changes the current working directory to the root
.Po
.Pa /
.Pc .
.Pp
Unless the argument
.Fa noclose
is non-zero,
.Fn daemon
will redirect standard input, standard output and standard error
to
.Pa /dev/null .
.Sh RETURN VALUES
On return 0 indicates success with -1 indicating error.
.Sh ERRORS
The function
.Fn daemon
may fail and set
.Va errno
for any of the errors specified for the library functions
.Xr fork 2
and
.Xr setsid 2 .
.Sh SEE ALSO
.Xr fork 2 ,
.Xr setsid 2
.Sh HISTORY
The
.Fn daemon
function first appeared in
.Bx 4.4 .
.Sh BUGS
.Fn daemon
uses
.Fn fork
as part of its tty detachment mechanism. Consequently the process id changes
when
.Fn daemon
is invoked. Processes employing
.Fn daemon
can not be reliably waited
upon until
.Fn daemon
has been invoked.