xref: /freebsd/usr.bin/nohup/nohup.1 (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)

.\" 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.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd June 26, 2023
.Dt NOHUP 1
.Os
.Sh NAME
.Nm nohup
.Nd invoke a utility immune to hangups
.Sh SYNOPSIS
.Nm
.Op Fl Fl
.Ar utility
.Op Ar arguments
.Sh DESCRIPTION
The
.Nm
utility invokes
.Ar utility
with its
.Ar arguments
and at this time sets the signal
.Dv SIGHUP
to be ignored.
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.
.Pp
Some shells may provide a builtin
.Nm
command which is similar or identical to this utility.
Consult the
.Xr builtin 1
manual page.
.Sh ENVIRONMENT
The following variables are utilized by
.Nm :
.Bl -tag -width flag
.It Ev HOME
If the output file
.Pa nohup.out
cannot be created in the current directory, the
.Nm
utility uses the directory named by
.Ev HOME
to create the file.
.It Ev PATH
Used to locate the requested
.Ar utility
if the name contains no
.Ql /
characters.
.El
.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 SEE ALSO
.Xr builtin 1 ,
.Xr csh 1 ,
.Xr timeout 1 ,
.Xr signal 3 ,
.Xr daemon 8
.Sh STANDARDS
The
.Nm
utility is expected to be
.St -p1003.2
compatible.
.Sh BUGS
Two or more instances of
.Nm
can append to the same file, which makes for a confusing output.