nohup(1)							   User Commands							  nohup(1)

NAME

       nohup - run a command immune to hangups

SYNOPSIS

       /usr/bin/nohup command [argument...]

       /usr/bin/nohup -p [-Fa] pid [pid...]

       /usr/bin/nohup -g [-Fa] gpid [gpid...]

       /usr/xpg4/bin/nohup command [argument...]

DESCRIPTION

       The nohup utility invokes the named command with the arguments supplied.  When the command is invoked, nohup arranges for the SIGHUP signal
       to be ignored by the process.

       When invoked with the -p or -g flags, nohup arranges for processes already running as identified by a list of process  IDs  or  a  list	of
       process group IDs to become immune to hangups.

       The  nohup  utility  can  be used when it is known that command will take a long time to run and the user wants to log out of the terminal.
       When a shell exits, the system sends its children SIGHUP signals, which by default cause them to be killed. All stopped, running, and back-
       ground  jobs  will  ignore SIGHUP and continue running, if their invocation is preceded by the nohup command or if the process programmati-
       cally has chosen to ignore SIGHUP.

       /usr/bin/nohup

	   Processes run by /usr/bin/nohup are immune to SIGHUP (hangup) and SIGQUIT (quit) signals.

       /usr/bin/nohup -p [-Fa]

	   Processes specified by ID are made immune to SIGHUP and SIGQUIT, and all output to the controlling terminal is redirected to nohup.out.
	   If  -F  is  specified, nohup will force control of each process. If -a is specified, nohup will change the signal disposition of SIGHUP
	   and SIGQUIT even if the process has installed a handler for either signal.

       /usr/bin/nohup -g [-Fa]

	   Every process in the same process group as the processes specified by ID are made immune to SIGHUP and SIGQUIT, and all output  to  the
	   controlling	terminal  is  redirected  to  nohup.out. If -F is specified, nohup will force control of each process. If -a is specified,
	   nohup will change the signal disposition of SIGHUP and SIGQUIT even if the process has installed a handler for either signal.

       /usr/xpg4/bin/nohup

	   Processes run by /usr/xpg4/bin/nohup are immune to SIGHUP.

	   The nohup utility does not arrange to make processes immune to a SIGTERM (terminate) signal, so unless they arrange	to  be	immune	to
	   SIGTERM or the shell makes them immune to SIGTERM, they will receive it.

	   If  nohup.out  is  not  writable in the current directory, output is redirected to $HOME/nohup.out. If a file is created, the file will
	   have read and write permission (600, see chmod(1)). If the standard error is a terminal, it is redirected to the standard output,  oth-
	   erwise it is not redirected. The priority of the process run by nohup is not altered.

OPTIONS

       The following options are supported:

       -a	Always changes the signal disposition of target processes. This option is valid only when specified with -p or -g.

       -F	Force. Grabs the target processes even if another process has control. This option is valid only when specified with -p or -g.

       -g	Operates on a list of process groups. This option is not valid with -p.

       -p	Operates on a list of processes. This option is not valid with -g.

OPERANDS

       The following operands are supported:

       pid	       A decimal process ID to be manipulated by nohup -p.

       pgid	       A decimal process group ID to be manipulated by nohup -g.

       command	       The  name  of a command that is to be invoked. If the command operand names any of the special shell_builtins(1) utilities,
		       the results are undefined.

       argument        Any string to be supplied as an argument when invoking the command operand.

EXAMPLES

       Example 1: Applying nohup to pipelines or command lists

       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. One can then issue:

       example$ nohup sh file

       and  the  nohup applies to everything in file. If the shell script file is to be executed often, then the need to type sh can be eliminated
       by giving file execute permission.

       Add an ampersand and the contents of file are run in the background with interrupts also ignored (see sh(1)):

       example$ nohup file &

       Example 2: Applying nohup -p to a process

       example$ long_running_command &
       example$ nohup -p `pgrep long_running_command`

       Example 3: Applying nohup -g to a process group

       example$ make &
       example$ ps -o sid -p $$
	  SID
       81079
       example$ nohup -g `pgrep -s 81079 make`

ENVIRONMENT VARIABLES

       See environ(5) for descriptions of the following environment variables that affect the execution of nohup: LANG, LC_ALL, LC_CTYPE,  LC_MES-
       SAGES, PATH, NLSPATH, and PATH.

       HOME	Determine the path name of the user's home directory: if the output file nohup.out cannot be created in the current directory, the
		nohup command will use the directory named by HOME to create the file.

EXIT STATUS

       The following exit values are returned:

       126	command was found but could not be invoked.

       127	An error occurred in nohup, or command could not be found

       Otherwise, the exit values of nohup will be those of the command operand.

FILES

       nohup.out	       The output file of the nohup execution if standard output is a terminal and if the current directory is writable.

       $HOME/nohup.out	       The output file of the nohup execution if standard output is a  terminal  and  if  the  current	directory  is  not
			       writable.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

   /usr/bin/nohup
       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+
       |CSI			     |enabled			   |
       +-----------------------------+-----------------------------+

   /usr/xpg4/bin/nohup
       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWxcu4			   |
       +-----------------------------+-----------------------------+
       |CSI			     |enabled			   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       batch(1),  chmod(1), csh(1), ksh(1), nice(1), pgrep(1), proc(1), ps(1), sh(1), shell_builtins(1), signal(3C), proc(4), attributes(5), envi-
       ron(5), standards(5)

WARNINGS

       If you are running the Korn shell (ksh(1)) as your login shell, and have nohup'ed jobs running when you attempt to log  out,  you  will	be
       warned with the message:

       You have jobs running.

       You will then need to log out a second time to actually log out. However, your background jobs will continue to run.

NOTES

       The  C-shell  (csh(1)) has a built-in command nohup that provides immunity from SIGHUP, but does not redirect output to nohup.out. Commands
       executed with `&' are automatically immune to HUP signals while in the background.

       nohup does not recognize command sequences. In the case of the following command,

       example$ nohup command1; command2

       the nohup utility applies only to command1. The command,

       example$ nohup (command1; command2)

       is syntactically incorrect.

SunOS 5.10							    16 Nov 2001 							  nohup(1)