caffeinate

CAFFEINATE(8)                System Manager's Manual               CAFFEINATE(8)

NAME
     caffeinate – prevent the system from sleeping on behalf of a utility

SYNOPSIS
     caffeinate [-disu] [-t timeout] [-w pid] [utility arguments...]

DESCRIPTION
     caffeinate creates assertions to alter system sleep behavior.  If no
     assertion flags are specified, caffeinate creates an assertion to prevent
     idle sleep.  If a utility is specified, caffeinate creates the assertions
     on the utility's behalf, and those assertions will persist for the duration
     of the utility's execution. Otherwise, caffeinate creates the assertions
     directly, and those assertions will persist until caffeinate exits.

     Available options:

     -d      Create an assertion to prevent the display from sleeping.

     -i      Create an assertion to prevent the system from idle sleeping.

     -m      Create an assertion to prevent the disk from idle sleeping.

     -s      Create an assertion to prevent the system from sleeping. This
             assertion is valid only when system is running on AC power.

     -u      Create an assertion to declare that user is active. If the display
             is off, this option turns the display on and prevents the display
             from going into idle sleep. If a timeout is not specified with '-t'
             option, then this assertion is taken with a default of 5 second
             timeout.

     -t      Specifies the timeout value in seconds for which this assertion has
             to be valid. The assertion is dropped after the specified timeout.
             Timeout value is not used when an utility is invoked with this
             command.

     -w      Waits for the process with the specified pid to exit. Once the the
             process exits, the assertion is also released.  This option is
             ignored when used with utility option.

EXAMPLE
     caffeinate -i make
        caffeinate forks a process, execs "make" in it, and holds an assertion
     that prevents idle sleep as long as that process is running.

SEE ALSO
     pmset(1)

LOCATION
     /usr/bin/caffeinate

Darwin                          November 9, 2012                          Darwin