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SCHED_SETPARAM(2)          Linux Programmer's Manual         SCHED_SETPARAM(2)
NAME
       sched_setparam, sched_getparam - set and get scheduling parameters
SYNOPSIS
       #include <sched.h>
       int sched_setparam(pid_t pid, const struct sched_param *param);
       int sched_getparam(pid_t pid, struct sched_param *param);
       struct sched_param {
           ...
           int sched_priority;
           ...
       };
DESCRIPTION
       sched_setparam()  sets  the  scheduling  parameters associated with the
       scheduling policy for the process identified by pid.  If pid  is  zero,
       then the parameters of the calling process are set.  The interpretation
       of the argument param depends on the scheduling policy of  the  process
       identified  by  pid.   See sched(7) for a description of the scheduling
       policies supported under Linux.
       sched_getparam() retrieves the scheduling parameters  for  the  process
       identified  by pid.  If pid is zero, then the parameters of the calling
       process are retrieved.
       sched_setparam() checks the validity of param for the scheduling policy
       of  the  thread.   The  value param->sched_priority must lie within the
       range given by sched_get_priority_min(2) and sched_get_priority_max(2).
       For a discussion of the  privileges  and  resource  limits  related  to
       scheduling priority and policy, see sched(7).
       POSIX systems on which sched_setparam() and sched_getparam() are avail-
       able define _POSIX_PRIORITY_SCHEDULING in <unistd.h>.
RETURN VALUE
       On success, sched_setparam() and sched_getparam() return 0.  On  error,
       -1 is returned, and errno is set appropriately.
ERRORS
       EINVAL Invalid arguments: param is NULL or pid is negative
       EINVAL (sched_setparam())  The  argument  param does not make sense for
              the current scheduling policy.
       EPERM  (sched_setparam()) The calling process does not have appropriate
              privileges (Linux: does not have the CAP_SYS_NICE capability).
       ESRCH  The process whose ID is pid could not be found.
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.
NOTES
       Scheduling  parameters  are in fact per-thread attributes on Linux; see
       sched(7).
SEE ALSO
       getpriority(2), nice(2), sched_get_priority_max(2),
       sched_get_priority_min(2), sched_getaffinity(2), sched_getscheduler(2),
       sched_setaffinity(2), sched_setattr(2), sched_setscheduler(2),
       setpriority(2), capabilities(7), sched(7)
COLOPHON
       This page is part of release 4.15 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                             2017-09-15                 SCHED_SETPARAM(2)