xref: /freebsd/lib/libc/gen/daemon.3 (revision e627b39baccd1ec9129690167cf5e6d860509655)
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32.\"	@(#)daemon.3	8.1 (Berkeley) 6/9/93
33.Dd June 9, 1993
34.Dt DAEMON 3
35.Os
36.Sh NAME
37.Nm daemon
38.Nd run in the background
39.Sh SYNOPSIS
40.Fd #include <stdlib.h>
41.Ft int
42.Fn daemon "int nochdir" "int noclose"
43.Sh DESCRIPTION
44.Pp
45The
46.Fn daemon
47function is for programs wishing to detach themselves from the
48controlling terminal and run in the background as system daemons.
49.Pp
50Unless the argument
51.Fa nochdir
52is non-zero,
53.Fn daemon
54changes the current working directory to the root (``/'').
55.Pp
56Unless the argument
57.Fa noclose
58is non-zero,
59.Fn daemon
60will redirect standard input, standard output and standard error
61to ``/dev/null''.
62.Sh ERRORS
63If an error occurs,
64.Fn daemon
65returns -1 and sets the global variable
66.Va errno
67to any of the errors specified for the library functions
68.Xr fork 2
69and
70.Xr setsid 2 .
71.Sh SEE ALSO
72.Xr fork 2 ,
73.Xr setsid 2
74.Sh HISTORY
75The
76.Fn daemon
77function first appeared in
78.Bx 4.4 .
79