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nohup(1)
NAME
  nohup - Runs a utility ignoring hangups and quits

SYNOPSIS
  nohup utility [argument...]

				     Note

       The C shell has a built-in version of the nohup command.	 If you are
       using the C shell, and want to guarantee that you are using the
       command described here, you must specify the full path /usr/bin/nohup.
       See the csh(1) reference page for a description of the built-in
       command.

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  nohup:  XCU5.0

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

OPTIONS
  None

OPERANDS
  utility
      The name of a command to be invoked.

  argument
      Optional arguments required by the utility specified for invokation.

DESCRIPTION
  The nohup command runs utility, ignoring all hangups and QUIT signals.  You
  can use this command to run programs in the background after logging off
  the system.  To run a nohup command in the background, add an & (ampersand)
  to the end of the command.

  If nohup output is redirected to a terminal or is not redirected at all,
  the output is appended to the file nohup.out.	 If the file is created, the
  permission bits are set to Owner Read and Owner Write (600). If nohup.out
  is not writable in the current directory, the output is redirected to
  $HOME/nohup.out.  If neither file can be created nor opened for appending,
  utility is not invoked.

  If standard error is a terminal, all output written to standard error is
  appended to the file receiving standard output.

  The nohup command accepts just one utility as an argument.  To apply nohup
  to a pipeline or list of commands, enter the pipeline or list in a shell
  script file.	Then run sh as utility using the following format:

  nohup sh -c file

  [Tru64 UNIX]	You can also assign the shell file execute permission and run
  it as the utility in the form:

  nohup file

NOTES
  The term utility, rather than the term command, describes the argument to
  nohup because shell compound commands, pipelines, special built-in
  programs, and the like, cannot be handled directly. In addition, the term
  utility includes user application programs and shell scripts, not just the
  standard utilities.

EXIT STATUS
  The nohup command returns the following exit values:

  126 The specified utility was found, but could not be invoked.

  127 The error occurred in the nohup utility or the specified utility could
      not be found.

  The exit status is otherwise that of the utility.

EXAMPLES
   1.  To leave a command running after logging out (sh only), enter:
	    nohup  find	 /  -print  &

       Shortly after you enter this, the following is displayed:
	    670
	    $ Sending output to nohup.out

       The process ID number changes to the background process started by the
       & (ampersand), in this case, 670.  The $ (dollar sign) is the shell
       prompt.	The message following informs you that the output from the
       find command is in the file nohup.out.
	    Sending output...

       You can log out after you see these messages, even if the find command
       has not finished yet.

       If you are using csh, the built-in command nohup is executed instead
       of the system command.  To execute the nohup system command, you must
       enter an absolute path.

   2.  To do the same, but redirect the standard output to a different file,
       enter:
	    nohup  find	 /  -print  >filenames	&

       This runs the find command and stores its output in a file named
       filenames. Now only the process ID and prompt are displayed.

       Wait for a second or two before logging out, because the nohup command
       takes a moment to start the command you specified. If you log out too
       quickly, utility may not run at all.  Once utility has started,
       logging out does not affect it.

   3.  To run more than one command, use a shell script.  For example, if you
       include the following shell script:
	    comm -23 fi4 fi5 | comm -23 - fi6 | join -a1 - fi7 > comm.out

       and name it ncomm, you can run nohup for all of the commands in ncomm
       by entering:
	    nohup sh ncomm

       If you assign ncomm Execute permission, you can obtain the same
       results by issuing the command:
	    nohup ncomm

       To run this command in the background, enter:
	    nohup ncomm &

ENVIRONMENT VARIABLES
  The following environment variables affect the execution of nohup:

  LANG
      Provides a default value for the internationalization variables that
      are unset or null. If LANG is unset or null, the corresponding value
      from the default locale is used.	If any of the internationalization
      variables contain an invalid setting, the utility behaves as if none of
      the variables had been defined.

  LC_ALL
      If set to a non-empty string value, overrides the values of all the
      other internationalization variables.

  LC_CTYPE
      Determines the locale for the interpretation of sequences of bytes of
      text data as characters (for example, single-byte as opposed to
      multibyte characters in arguments).

  LC_MESSAGES
      Determines the locale for the format and contents of diagnostic
      messages written to standard error.

  NLSPATH
      Determines the location of message catalogues for the processing of
      LC_MESSAGES.

  PATH
      Determines the search path that will be used to locate the command to
      be invoked.

FILES
  nohup.out
      Standard output and standard error file for nohup.

SEE ALSO
  Commands:  csh(1), ksh(1), nice(1), Bourne shell sh(1b), POSIX shell sh(1p)

  Functions:  sigaction(2)

  Standards:  standards(5)

Index for Section 1

Alphabetical listing for N

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