nohup - run a command immune to hangups
nohup command [arguments]
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.
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
If any internationalization variable contains an invalid setting,
nohup behaves as if all internationalization variables are set to "C".
International Code Set Support
Single- and multi-byte character code sets are supported.
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
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 Release 11i: November 2000
tbl ofile | eqn | nroff >>>> nfile
Be careful to place punctuation properly. For example, in the command
nohup command1; command2
nohup applies only to command1. To correct the problem, use the
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&&&&
nohup cpio -o <<<<list >>>>/dev/rmt/c0t0d0BEST 2>>>>errors&&&&
puts the error messages into file errors.
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
chmod(1), nice(1), sh(1), signal(5).
nohup: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2
Hewlett-Packard Company - 2 - HP-UX Release 11i: November 2000