Manual Pages for UNIX Operating System command usage for man sched_setparam

Standard C Library Functions                   sched_setparam(3C)



NAME
     sched_setparam - set scheduling parameters

SYNOPSIS
     #include 

     int sched_setparam(pid_t pid, const struct sched_param *param);


DESCRIPTION
     The sched_setparam() function sets the scheduling parameters
     of  the  process specified by pid to the values specified by
     the sched_param structure pointed to by param. The value  of
     the  sched_priority  member  in the sched_param structure is
     any integer within the  inclusive  priority  range  for  the
     current  scheduling  policy of the process specified by pid.
     Higher numerical values for the  priority  represent  higher
     priorities. If the value of pid is negative, the behavior of
     the sched_setparam() function is unspecified.


     If a process specified by pid exists and if the calling pro-
     cess  has  permission, the scheduling parameters will be set
     for the process whose process ID is equal to pid.  The  real
     or  effective  user ID of the calling process must match the
     real or saved (from exec(2)) user ID of the  target  process
     unless  the  effective  user ID of the calling process is 0.
     See Intro(2).


     If pid is zero, the scheduling parameters will  be  set  for
     the calling process.


     The target process, whether it is running  or  not  running,
     resumes  execution  after  all  other  runnable processes of
     equal or greater priority have been scheduled to run.


     If the priority of the process specified by the pid argument
     is  set higher than that of the lowest priority running pro-
     cess and if the specified process is ready to run, the  pro-
     cess  specified by the pid argument preempts a lowest prior-
     ity running  process.  Similarly,  if  the  process  calling
     sched_setparam()  sets  its  own priority lower than that of
     one or more other non-empty process lists, then the  process
     that  is the head of the highest priority list also preempts
     the calling process. Thus, in either case,  the  originating
     process  might not receive notification of the completion of
     the requested priority change until the higher priority pro-
     cess has executed.




SunOS 5.11           Last change: 1 Apr 2008                    1






Standard C Library Functions                   sched_setparam(3C)



RETURN VALUES
     If successful, the sched_setparam() function returns 0.


     If the call to sched_setparam() is unsuccessful, the  prior-
     ity  remains unchanged, and the function returns -1 and sets
     errno to indicate the error.

ERRORS
     The sched_setparam() function will fail if:

     EINVAL    One or more of the requested scheduling parameters
               is  outside  the  range defined for the scheduling
               policy of the specified pid.


     EPERM     The requesting process does not have permission to
               set  the  scheduling  parameters for the specified
               process,  or  does  not   have   the   appropriate
               privilege to invoke sched_setparam().


     ESRCH     No process can  be  found  corresponding  to  that
               specified by pid.


ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    | ATTRIBUTE TYPE              | ATTRIBUTE VALUE             |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | MT-Level                    | MT-Safe                     |
    |_____________________________|_____________________________|
    | Standard                    | See standards(5).           |
    |_____________________________|_____________________________|


SEE ALSO
     Intro(2),     exec(2),     librt(3LIB),      sched.h(3HEAD),
     sched_getparam(3C),                  sched_getscheduler(3C),
     sched_setscheduler(3C), attributes(5), standards(5)








SunOS 5.11           Last change: 1 Apr 2008                    2