schedsetparam(2)                                            schedsetparam(2)



NAME
     schedsetparam - set the scheduling parameters of a process

C SYNOPSIS
     #include <sched.h>

     int schedsetparam (pidt pid, const struct schedparam *param);


DESCRIPTION

     The schedsetparam system call is used to set the scheduling policy

     parameters for the process specified by pid.  If pid is set to zero, then

     the scheduling parameters of the calling process will be affected.


     The scheduling parameters of pid are specified by the parameter structure

     at address param.


     The priority of the target process may be modified by setting the desired

     priority value in the sched_priority field of the param structure.


     Unlike IRIX 6.2 and earlier releases, processes having a higher numerical

     priority value are more important than processes having a lower numerical

     priority value. Specified priorities remain fixed, unless explicitly

     changed in the future, and are not affected by priority aging schemes.


     The priority range for these scheduling policies may be obtained via the

     schedgetprioritymin(2) and schedgetprioritymax(2) function calls.

     However, arbitrary priority values within the range should not be used.

     Developers must consider the needs of the application and how it should

     interact with the rest of the system, before selecting a real-time

     priority.  For more information, see the "Real-Time Priority Band"

     section of realtime(5).


     The calling process must have superuser permissions to successfully

     execute schedsetparam.


     If the process specified by pid is currently executing or is in a

     runnable state, schedsetparam causes the process to be rescheduled at

     its new priority.


     If pid refers to a POSIX thread process [see pthreads(3P)] then this call

     retrieves the scheduling policy parameters that are shared by process

     scope threads.


     schedsetparam will fail if one or more of the following are true:


     [EINVAL]       One of the specified parameters at address param are out

                    of range or scope.


     [EPERM]        The calling process does not have superuser permissions.







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schedsetparam(2)                                            schedsetparam(2)



     [ESRCH]        The process specified by pid does not exist.

SEE ALSO
     realtime(5), sched_getparam(2), sched_getscheduler(2),
     sched_setscheduler(2), sched_yield(2), sched_get_priority_max(2),
     sched_get_priority_min(2), sched_rr_get_interval(2), pthreads(5)

DIAGNOSTICS
     Upon successful completion, a value of 0 is returned to the calling
     process. Otherwise, a value of -1 is returned and errno is set to
     indicate the error.












































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