NICE(2) System Calls Manual NICE(2)
nice - set program priority
The scheduling priority of the process is augmented by incr. Positive
priorities get less service than normal. Priority 10 is recommended to
users who wish to execute long-running programs without flak from the
Negative increments are ignored except on behalf of the super-user.
The priority is limited to the range -20 (most urgent) to 20 (least).
The priority of a process is passed to a child process by fork(2). For
a privileged process to return to normal priority from an unknown
state, nice should be called successively with arguments -40 (goes to
priority -20 because of truncation), 20 (to get to 0), then 0 (to main-
tain compatibility with previous versions of this call).
(nice = 34.)
(priority in r0)