NAME
nice —
set program scheduling
priority
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
int
nice(
int
incr);
DESCRIPTION
The
nice() function obtains the scheduling priority of the
process from the system and sets it to the priority value specified in
incr. The priority is a value in the range -20 to 20.
The default priority is 0; lower priorities cause more favorable scheduling.
Only a process with appropriate privileges may lower priorities.
Children inherit the priority of their parent processes via
fork(2).
RETURN VALUES
Upon successful completion,
nice() returns the new nice value
minus
NZERO
. Otherwise, -1 is returned, the process'
nice value is not changed, and
errno is set to indicate
the error.
ERRORS
The
nice() function will fail if:
-
-
- [
EPERM
]
- The incr argument is negative and the
caller does not have appropriate privileges.
SEE ALSO
nice(1),
fork(2),
setpriority(2),
renice(8)
STANDARDS
The
nice() function conforms to
X/Open
Portability Guide Issue 4, Version 2 (“XPG4.2”).
HISTORY
A
nice() syscall appeared in
Version 6
AT&T UNIX.