NAME

       pthread_attr_setschedparam,  pthread_attr_getschedparam  -  set/get  scheduling  parameter
       attributes in thread attributes object

SYNOPSIS

       #include <pthread.h>

       int pthread_attr_setschedparam(pthread_attr_t *attr,
                                      const struct sched_param *param);
       int pthread_attr_getschedparam(const pthread_attr_t *attr,
                                      struct sched_param *param);

       Compile and link with -pthread.

DESCRIPTION

       The pthread_attr_setschedparam() function sets the scheduling parameter attributes of  the
       thread attributes object referred to by attr to the values specified in the buffer pointed
       to by param.  These attributes determine the scheduling parameters  of  a  thread  created
       using the thread attributes object attr.

       The pthread_attr_getschedparam() returns the scheduling parameter attributes of the thread
       attributes object attr in the buffer pointed to by param.

       Scheduling parameters are maintained in the following structure:

           struct sched_param {
               int sched_priority;     /* Scheduling priority */
           };

       As can be seen, only one scheduling parameter is supported.  For details of the  permitted
       ranges for scheduling priorities in each scheduling policy, see sched(7).

       In  order  for  the  parameter setting made by pthread_attr_setschedparam() to have effect
       when calling pthread_create(3), the caller must use pthread_attr_setinheritsched(3) to set
       the inherit-scheduler attribute of the attributes object attr to PTHREAD_EXPLICIT_SCHED.

RETURN VALUE

       On success, these functions return 0; on error, they return a nonzero error number.

ERRORS

       pthread_attr_setschedparam() can fail with the following error:

       EINVAL The  priority  specified  in  param  does not make sense for the current scheduling
              policy of attr.

       POSIX.1 also documents an ENOTSUP error for pthread_attr_setschedparam().  This  value  is
       never  returned  on  Linux (but portable and future-proof applications should nevertheless
       handle this error return value).

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────────────────────────┬───────────────┬─────────┐
       │Interface                     │ Attribute     │ Value   │
       ├──────────────────────────────┼───────────────┼─────────┤
       │pthread_attr_setschedparam(), │ Thread safety │ MT-Safe │
       │pthread_attr_getschedparam()  │               │         │
       └──────────────────────────────┴───────────────┴─────────┘

CONFORMING TO

       POSIX.1-2001, POSIX.1-2008.

NOTES

       See  pthread_attr_setschedpolicy(3) for a list of the thread scheduling policies supported
       on Linux.

EXAMPLE

       See pthread_setschedparam(3).

SEE ALSO

       sched_get_priority_min(2), pthread_attr_init(3), pthread_attr_setinheritsched(3),
       pthread_attr_setschedpolicy(3), pthread_create(3), pthread_setschedparam(3),
       pthread_setschedprio(3), pthreads(7), sched(7)

COLOPHON

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       project, information about reporting bugs, and the latest version of this page, can be
       found at http://www.kernel.org/doc/man-pages/.