DragonFly On-Line Manual Pages
NICE(1) DragonFly General Commands Manual NICE(1)
nice -- execute a utility at an altered scheduling priority
nice [-n increment] utility [argument ...]
The nice utility runs utility at an altered scheduling priority, by
incrementing its ``nice'' value by the specified increment, or a default
value of 10. The lower the nice value of a process, the higher its
The superuser may specify a negative increment in order to run a utility
with a higher scheduling priority.
Some shells may provide a builtin nice command which is similar or iden-
tical to this utility. Consult the builtin(1) manual page.
If utility is invoked, the exit status of nice is the exit status of
An exit status of 126 indicates utility was found, but could not be exe-
cuted. An exit status of 127 indicates utility could not be found.
$ nice -n 5 date
Execute utility `date' at priority 5 assuming the priority of the shell
# nice -n 16 nice -n -35 date
Execute utility `date' at priority -19 assuming the priority of the shell
is 0 and you are the super-user.
The traditional -increment option has been deprecated but is still sup-
builtin(1), csh(1), idprio(1), rtprio(1), getpriority(2), setpriority(2),
The nice utility conforms to IEEE Std 1003.1-2001 (``POSIX.1'').
A nice utility appeared in Version 4 AT&T UNIX.
DragonFly 5.5 June 6, 1993 DragonFly 5.5
NICE(3) DragonFly Library Functions Manual NICE(3)
nice -- set program scheduling priority
Standard C Library (libc, -lc)
This interface is obsoleted by setpriority(2).
The nice() function obtains the scheduling priority of the process from
the system and sets it to the priority value specified in incr. The pri-
ority is a value in the range -20 to 20. The default priority is 0;
lower priorities cause more favorable scheduling. Only the super-user
may lower priorities.
Children inherit the priority of their parent processes via fork(2).
Upon successful completion, nice() returns the new nice value. Other-
wise, -1 is returned, the process' nice value is not changed, and errno
is set appropriately.
The nice() function will fail if:
[EPERM] The incr argument is negative and the calling process
does not have super-user privileges.
nice(1), fork(2), setpriority(2), renice(8)
A nice() syscall appeared in Version 6 AT&T UNIX.
DragonFly 5.5 June 25, 2009 DragonFly 5.5