.\"	$NetBSD: nohup.1,v 1.13 2005/07/14 22:16:39 wiz Exp $
.\"
.\" Copyright (c) 1989, 1990, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the Institute of Electrical and Electronics Engineers, Inc.
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.\" modification, are permitted provided that the following conditions
.\" are met:
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.\"    may be used to endorse or promote products derived from this software
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.\"	@(#)nohup.1	8.1 (Berkeley) 6/6/93
.\"
.Dd July 15, 2005
.Dt NOHUP 1
.Os
.Sh NAME
.Nm nohup
.Nd invoke a command immune to hangups
.Sh SYNOPSIS
.Nm
.Ar utility
.Op Ar arg ...
.Sh DESCRIPTION
The
.Nm
command allows the specified utility to be protected from termination
if the user should become logged out
(for example, due to a modem line or TCP/IP connection being dropped).
To do this,
.Nm
sets the
.Dv SIGHUP
.Xr signal 3
.Pq Dq terminal line hangup
to be ignored,
then executes
.Ar utility
along with any arguments.
.Pp
If the standard output is a terminal, the standard output is
appended to the file
.Pa nohup.out
in the current directory.
If standard error is a terminal, it is directed to the same place
as the standard output.
If the output file
.Pa nohup.out
cannot be created in the current directory,
.Nm
attempts to create the file in the user's home directory.
If the file
.Pa nohup.out
cannot be created,
either in the current directory or the user's home directory,
.Nm
will exit without invoking
.Ar utility ,
with an exit value as described below.
.Sh EXIT STATUS
The
.Nm
utility exits with one of the following values:
.Bl -tag -width Ds
.It 126
The
.Ar utility
was found but could not be invoked.
.It 127
The
.Ar utility
could not be found or an error occurred in
.Nm .
.El
.Pp
Otherwise, the exit status of
.Nm
will be that of
.Ar utility .
.Sh ENVIRONMENT
The following variable is used by
.Nm .
.Bl -tag -width flag
.It Ev HOME
User's home directory.
.El
.Sh SEE ALSO
.Xr signal 3
.Sh STANDARDS
The
.Nm
command is expected to be
.St -p1003.2
compatible.