freebsd-nq/lib/libc/gen/daemon.3

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.\" Copyright (c) 1993
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.\" @(#)daemon.3 8.1 (Berkeley) 6/9/93
.\" $FreeBSD$
.\"
.Dd June 9, 1993
.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 (``/'').
.Pp
Unless the argument
.Fa noclose
is non-zero,
.Fn daemon
will redirect standard input, standard output and standard error
to ``/dev/null''.
.Sh ERRORS
If an error occurs,
.Fn daemon
returns -1 and sets the global variable
.Va errno
to 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 .