The nice utility invokes command, requesting that it be run with a different system scheduling priority. The priocntl(1) command is a more general interface to scheduler functions.
The invoking process (generally the user's shell) must be in a scheduling class that supports nice.
If the C shell (see csh(1)) is used, the full path of the command must be specified; otherwise, the csh built-in version of nice will be invoked. See csh Builtin below.
If nice executes commands with arguments, it uses the default shell /usr/bin/sh (see sh(1)).
If nice executes commands with arguments, it uses /usr/xpg4/bin/sh (see ksh(1)).
nice is also a csh built-in command with behavior different from the utility versions. See csh(1) for description.
The following options are supported:
increment must be in the range 1-19; if not specified, an increment of 10 is assumed. An increment greater than 19 is equivalent to 19.
The super-user may run commands with priority higher than normal by using a negative increment such as –10. A negative increment assigned by an unprivileged user is ignored.
The following operands are supported:
The name of a command that is to be invoked. If command names any of the special built-in utilities (see shell_builtins(1)), the results are undefined.
Any string to be supplied as an argument when invoking command.
See environ(5) for descriptions of the following environment variables that affect the execution of nice: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES, PATH, and NLSPATH.
If command is invoked, the exit status of nice will be the exit status of command. Otherwise, nice will exit with one of the following values:
An error occurred.
command was found but could not be invoked.
command could not be found.
See attributes(5) for descriptions of the following attributes: