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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 4.16 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)