Multithreaded Programming Guide


Use pthread_attr_setschedpolicy(3THR) to set the scheduling policy. The POSIX draft standard specifies scheduling policy attributes of SCHED_FIFO (first-in-first-out), SCHED_RR (round-robin), or SCHED_OTHER (an implementation-defined method).

SCHED_FIFO and SCHED_RR are optional in POSIX, and are supported for real time bound threads only.

Currently, only the Solaris SCHED_OTHER, time-sharing, default value is supported in pthreads. For a discussion of scheduling, see the section "Scheduling".


int	pthread_attr_setschedpolicy(pthread_attr_t *tattr, int policy);
#include <pthread.h>

pthread_attr_t tattr;
int policy;
int ret;

/* set the scheduling policy to SCHED_OTHER */
ret = pthread_attr_setschedpolicy(&tattr, SCHED_OTHER);

Return Values

Returns zero after completing successfully. Any other returned value indicates that an error occurred. When either of the following conditions occurs, the function fails and returns the corresponding value.


An attempt was made to set tattr to a value that is not valid.


An attempt was made to set the attribute to an unsupported value.