sunos man page for nice

nice(3UCB)					     SunOS/BSD Compatibility Library Functions						nice(3UCB)

NAME
       nice - change priority of a process

SYNOPSIS
       /usr/ucb/cc[ flag ... ] file ...
       #include<unistd.h>

       int nice(incr);
       int incr;

DESCRIPTION
       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 undue impact on system performance.

       Negative increments are illegal, except when specified by the privileged user. The priority is limited to the range -20 (most urgent) to 20
       (least). Requests for values above or below these limits result in the scheduling priority being set to the corresponding limit.

       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
       maintain compatibility with previous versions of this call).

RETURN VALUES
       Upon successful completion, nice() returns 0. Otherwise, a value of -1 is returned and errno is set to indicate the error.

ERRORS
       The priority is not changed if:

       EPERM	       The value of incr specified was negative, and the effective user ID is not the privileged user.

SEE ALSO
       nice(1), renice(1), fork(2), priocntl(2), getpriority(3C)

NOTES
       Use of these interfaces should be restricted to only applications written on BSD platforms.  Use of these interfaces with any of the system
       libraries or in multi-threaded applications is unsupported.

SunOS 5.10							    12 Feb 1993 							nice(3UCB)