Gets and sets the schedpolicy attribute (REALTIME THREADS).
#include <pthread.h>
#include <time.h>
int pthread_attr_getschedpolicy(const pthread_attr_t *restrict attr,
int *restrict policy);
int pthread_attr_setschedpolicy(pthread_attr_t *attr, int policy);The pthread_attr_getschedpolicy() and pthread_attr_setschedpolicy() functions, respectively, get and set the schedpolicy attribute in the attr argument.
The supported values of policy include SCHED_FIFO, SCHED_RR, and SCHED_OTHER, which are defined in the <sched.h> header. When threads executing with the scheduling policy SCHED_FIFO, SCHED_RR, or SCHED_SPORADIC are waiting on a mutex, they acquire the mutex in priority order when the mutex is unlocked.
After these attributes have been set, a thread can be created with the specified attributes using pthread_create(). Using these routines does not affect the current running thread.
If successful, the pthread_attr_getschedpolicy() and pthread_attr_setschedpolicy() functions return 0; otherwise, an error number is returned to indicate the error.
The pthread_attr_setschedpolicy() function might fail if:
| Item | Description |
|---|---|
| EINVAL | The value of policy is not valid. |
| ENOTSUP | An attempt was made to set the attribute to an unsupported value. |
These functions do not return an error code of EINTR.