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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | SEE ALSO | COLOPHON |
SCHED_GET_PRIORITY_MAX(2) Linux Programmer's ManualSCHED_GET_PRIORITY_MAX(2)
sched_get_priority_max, sched_get_priority_min - get static priority
range
#include <sched.h>
int sched_get_priority_max(int policy);
int sched_get_priority_min(int policy);
sched_get_priority_max() returns the maximum priority value that can
be used with the scheduling algorithm identified by policy.
sched_get_priority_min() returns the minimum priority value that can
be used with the scheduling algorithm identified by policy.
Supported policy values are SCHED_FIFO, SCHED_RR, SCHED_OTHER,
SCHED_BATCH, SCHED_IDLE, and SCHED_DEADLINE. Further details about
these policies can be found in sched(7).
Processes with numerically higher priority values are scheduled
before processes with numerically lower priority values. Thus, the
value returned by sched_get_priority_max() will be greater than the
value returned by sched_get_priority_min().
Linux allows the static priority range 1 to 99 for the SCHED_FIFO and
SCHED_RR policies, and the priority 0 for the remaining policies.
Scheduling priority ranges for the various policies are not
alterable.
The range of scheduling priorities may vary on other POSIX systems,
thus it is a good idea for portable applications to use a virtual
priority range and map it to the interval given by
sched_get_priority_max() and sched_get_priority_min POSIX.1 requires
a spread of at least 32 between the maximum and the minimum values
for SCHED_FIFO and SCHED_RR.
POSIX systems on which sched_get_priority_max() and
sched_get_priority_min() are available define
_POSIX_PRIORITY_SCHEDULING in <unistd.h>.
On success, sched_get_priority_max() and sched_get_priority_min()
return the maximum/minimum priority value for the named scheduling
policy. On error, -1 is returned, and errno is set appropriately.
EINVAL The argument policy does not identify a defined scheduling
policy.
POSIX.1-2001, POSIX.1-2008.
sched_getaffinity(2), sched_getparam(2), sched_getscheduler(2),
sched_setaffinity(2), sched_setparam(2), sched_setscheduler(2),
sched(7)
This page is part of release 4.12 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
Linux 2015-08-08 SCHED_GET_PRIORITY_MAX(2)
Pages that refer to this page: sched_setaffinity(2), sched_setattr(2), sched_setparam(2), sched_setscheduler(2), syscalls(2), pthread_attr_setschedparam(3), pthread_setschedparam(3), pthread_setschedprio(3), sched(7)