nohup invocation (GNU Coreutils 9.0)
23.4 nohup: Run a command immune to hangups
nohup runs the given
command with hangup signals ignored, so that the command can continue running in the background after you log out. Synopsis:
nohup command [arg]…
If standard input is a terminal, redirect it so that terminal sessions do not mistakenly consider the terminal to be used by the command. Make the substitute file descriptor unreadable, so that commands that mistakenly attempt to read from standard input can report an error. This redirection is a GNU extension; programs intended to be portable to non-GNU hosts can use ‘
nohup command [arg]… 0>/dev/null’ instead.
If standard output is a terminal, the command’s standard output is appended to the file
nohup.out; if that cannot be written to, it is appended to the file
$HOME/nohup.out; and if that cannot be written to, the command is not run. Any
$HOME/nohup.out file created by
nohup is made readable and writable only to the user, regardless of the current umask settings.
If standard error is a terminal, it is normally redirected to the same file descriptor as the (possibly-redirected) standard output. However, if standard output is closed, standard error terminal output is instead appended to the file
$HOME/nohup.out as above.
To capture the command’s output to a file other than
nohup.out you can redirect it. For example, to capture the output of
nohup make > make.log
nohup does not automatically put the command it runs in the background; you must do that explicitly, by ending the command line with an ‘
nohup does not alter the niceness of
nice for that, e.g., ‘
nohup nice command’.
command must not be a special built-in utility (see Special built-in utilities).
The only options are
--version. See Common options. Options must precede operands.
125 if nohup itself fails, and POSIXLY_CORRECT is not set 126 if command is found but cannot be invoked 127 if command cannot be found the exit status of command otherwise
POSIXLY_CORRECT is set, internal failures give status 127 instead of 125.