nohup - phpMan

File: coreutils.info,  Node: nohup invocation,  Next: stdbuf invocation,  Prev: nice invocation,  Up: Modified command invocation
23.4 'nohup': Run a command immune to hangups
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'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 '$HOME/nohup.out'; and if that cannot be written
to, the command is not run.  Any 'nohup.out' or '$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 'nohup.out' or '$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 'make':
     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 '&'.  Also, 'nohup' does not alter the niceness of COMMAND; use
'nice' for that, e.g., 'nohup nice COMMAND'.
   COMMAND must not be a special built-in utility (*note Special
built-in utilities::).
   The only options are '--help' and '--version'.  *Note Common
options::.  Options must precede operands.
   Exit status:
     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
   If 'POSIXLY_CORRECT' is set, internal failures give status 127
instead of 125.