pthread_scheduling.c

#include <pthread.h>
#include <stdio.h>

#define NUM_THREADS 5

void *runner(void *param);

int main(int argc, char *argv[])
{
    int i, scope;
    pthread_t tid[NUM_THREADS];
    pthread_attr_t attr;

    /* get the default attributes */
    pthread_attr_init(&attr);

    /* first inquire on the current scope */
    if(pthread_attr_getscope(&attr, &scope) != 0){
        fprintf(stderr, "Unable to get scheduling scope\n");
    }else{
        if(scope == PTHREAD_SCOPE_PROCESS) printf("PTHREAD_SCOPE_PROCESS\n");
        else if(scope == PTHREAD_SCOPE_SYSTEM) printf("PTHREAD_SCOPE_SYSTEM\n");
        else fprintf(stderr, "Illegal scope value\n");
    }

    /* set the scheduling algorithm to PCS or SCS  */
    pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM);

    /* create the threads */
    for(i = 0;i < NUM_THREADS; i++){
        pthread_create(&tid[i], &attr, runner, NULL);
    }

    /* now join on each thread */
    for(i = 0; i < NUM_THREADS; i++){
        pthread_join(tid[i], NULL);
    }
}

/* Each thread will begin control in this function */
void *runner(void *param)
{
    printf("Inside runner\n");

    pthread_exit(0);
}