nohup(1) nohup(1)
NAME [Toc] [Back]
nohup - run a command immune to hangups
SYNOPSIS [Toc] [Back]
nohup command [arguments]
DESCRIPTION [Toc] [Back]
nohup executes command with hangups and quits ignored. If output is
not redirected by the user, both standard output and standard error
are sent to nohup.out. If nohup.out is not writable in the current
directory, output is redirected to $HOME/nohup.out; otherwise, nohup
fails. If a file is created, the file's permission bits will be set to
S_IRUSR | S_IWUSR.
If output from nohup is redirected to a terminal, or is not redirected
at all, the output is sent to nohup.out.
EXTERNAL INFLUENCES [Toc] [Back]
Environment Variables
LC_MESSAGES determines the language in which messages are displayed.
If LC_MESSAGES is not specified in the environment or is set to the
empty string, the value of LANG is used as a default for each
unspecified or empty variable. If LANG is not specified or is set to
the empty string, a default of "C" (see lang(5)) is used instead of
LANG.
If any internationalization variable contains an invalid setting,
nohup behaves as if all internationalization variables are set to "C".
See environ(5).
International Code Set Support [Toc] [Back]
Single- and multi-byte character code sets are supported.
EXAMPLES [Toc] [Back]
It is frequently desirable to apply nohup to pipelines or lists of
commands. This can be done only by placing pipelines and command
lists in a single file, called a shell script. To run the script
using nohup:
nohup sh file
nohup features apply to the entire contents of file. If the shell
script file is to be executed often, the need to type sh can be
eliminated by setting execute permission on file. The script can also
be run in the background with interrupts ignored (see sh(1)):
nohup file &
file typically contains normal keyboard command sequences that one
would want to continue running in case the terminal disconnects, such
Hewlett-Packard Company - 1 - HP-UX 11i Version 2: August 2003
nohup(1) nohup(1)
as:
tbl ofile | eqn | nroff > nfile
WARNINGS [Toc] [Back]
Be careful to place punctuation properly. For example, in the command
form:
nohup command1; command2
nohup applies only to command1. To correct the problem, use the
command form:
nohup (command1; command2)
Be careful of where standard error is redirected. The following
command may put error messages on tape, making it unreadable:
nohup cpio -o <list >/dev/rmt/c0t0d0BEST&
whereas
nohup cpio -o <list >/dev/rmt/c0t0d0BEST 2>errors&
puts the error messages into file errors.
EXIT STATUS [Toc] [Back]
The following exit values are returned:
126 The command specified by command was found but could
not be invoked
127 An error occurred in the nohup utility or the specified
command could not be found
Otherwise, the exit status of nohup will be that of the command
specified.
SEE ALSO [Toc] [Back]
chmod(1), nice(1), sh(1), signal(5).
STANDARDS CONFORMANCE [Toc] [Back]
nohup: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2
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