Click this button to go to the index for this section.

nice(1)
NAME
  nice - Runs a command at a different priority

SYNOPSIS
  Current syntax


  nice [-n priority] command [argument...]

  Obsolescent syntax


  nice [-priority] command [argument...]

				     Note

       The C shell has a built-in version of the nice 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/nice.
       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:

  nice:	 XPG4, XPG4-UNIX

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

OPTIONS
  -n priority
      Specifies how the system scheduling priority of the executed utility is
      adjusted.	 The priority argument is a positive or negative decimal
      integer.

      Positive priority values cause a lower or unchanged system scheduling
      priority.

      Negative priority values might require appropriate privileges and cause
      a higher or unchanged system scheduling priority.

  -priority
      Specifies how the system scheduling priority of the executed utility is
      adjusted.	 (Obsolescent)




OPERANDS
  command
      The name of a utility that is to be invoked.

  argument
      Any string to be supplied as an argument to the utility named by the
      command operand.

DESCRIPTION
  The nice command lets you run the specified command at a lower priority.
  The value of priority can range from 1 to 19, with 19 being the lowest
  priority.  The default value of priority is 10.

  [DIGITAL]  If you have superuser authority, you can run commands at a
  higher priority by specifying priority as a negative number; for example,
  -10.

NOTES
  The csh command contains a built-in subcommand named nice.  The command and
  subcommand do not necessarily work the same way.  For information on the
  subcommand, see the csh command.

EXIT STATUS
  The nice command returns the following exit values:

  1-125
      An error occurred in the nice utility.

  126 The specified command was found but could not be invoked.

  127 The specified command could not be found.

EXAMPLES
   1.  To run a low priority command in the background, enter:
	    nice  cc  -c  *.c  &

       This runs the command cc -c *.c at low priority in the background.
       Your terminal is free so that you can run other commands while cc is
       running. See the sh command for details about starting background
       processes with an & (ampersand).

   2.  To specify a very low priority, enter:
	    nice -n 15	cc  -c	*.c  &

       This runs cc in the background at a priority that is even lower than
       the default priority set by nice.

   3.  To specify a very high priority (ksh and sh only), enter:
	    nice -n -10	 wall  <<end
	    System shutdown in 2 minutes!
	    end

       This runs wall at a higher priority than all user processes. Doing
       this slows down everything else running on the system. If you do not
       have superuser authority when you run this command, then the wall
       command runs at the normal priority.

       The <<end and end arguments define a Here Document, which uses the
       text entered before the end line as standard input for the command.
       For more details, see the Inline Input (Here) Documents section on the
       sh(1) reference page.






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

  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 used to locate the command invoked.

SEE ALSO
  Commands:  csh(1), nohup(1), renice(8)

  Functions:  nice(3), setpriority(2)

  Standards:  standards(5)