gen/daemon.3

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  32 .\"     @(#)daemon.3    8.1 (Berkeley) 6/9/93
  33 .\" $FreeBSD: src/lib/libc/gen/daemon.3,v 1.10 2001/10/01 16:08:50 ru Exp $
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  35 .Dd June 9, 1993
  36 .Dt DAEMON 3
  37 .Os
  38 .Sh NAME
  39 .Nm daemon
  40 .Nd run in the background
  41 .Sh LIBRARY
  42 .Lb libc
  43 .Sh SYNOPSIS
  44 .In stdlib.h
  45 .Ft int
  46 .Fn daemon "int nochdir" "int noclose"
  47 .Sh DESCRIPTION
  48 The
  49 .Fn daemon
  50 function is for programs wishing to detach themselves from the
  51 controlling terminal and run in the background as system daemons.
  52 .Pp
  53 Unless the argument
  54 .Fa nochdir
  55 is non-zero,
  56 .Fn daemon
  57 changes the current working directory to the root (``/'').
  58 .Pp
  59 Unless the argument
  60 .Fa noclose
  61 is non-zero,
  62 .Fn daemon
  63 will redirect standard input, standard output and standard error
  64 to ``/dev/null''.
  65 .Sh ERRORS
  66 If an error occurs,
  67 .Fn daemon
  68 returns -1 and sets the global variable
  69 .Va errno
  70 to any of the errors specified for the library functions
  71 .Xr fork 2
  72 and
  73 .Xr setsid 2 .
  74 .Sh SEE ALSO
  75 .Xr fork 2 ,
  76 .Xr setsid 2
  77 .Sh HISTORY
  78 The
  79 .Fn daemon
  80 function first appeared in
  81 .Bx 4.4 .