caffeinate - inhibit desktop idleness while a command runs
Caffeinate runs the given command and prevents the desktop becoming idle while
it is run, hence stops screen savers or power-saving activating even if the
machine is not being used.
It is usually more convenient to use the fully-automatic caffeine(1); caffeinate
may be useful when it is impractical or impossible to run a program in
full-screen mode, or to prevent automatic suspend kicking in during a
long-running unattended command, such as a system update.
Reuben Thomas <email@example.com>