| 12345678910111213141516171819202122232425262728293031 | #include <stdio.h>
#include "mythreads.h"
pthread_mutex_t g = PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m1 = PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t m2 = PTHREAD_MUTEX_INITIALIZER;
void* worker(void* arg) {
    Pthread_mutex_lock(&g);
    if ((long long) arg == 0) {
	Pthread_mutex_lock(&m1);
	Pthread_mutex_lock(&m2);
    } else {
	Pthread_mutex_lock(&m2);
	Pthread_mutex_lock(&m1);
    }
    Pthread_mutex_unlock(&m1);
    Pthread_mutex_unlock(&m2);
    Pthread_mutex_unlock(&g);
    return NULL;
}
int main(int argc, char *argv[]) {
    pthread_t p1, p2;
    Pthread_create(&p1, NULL, worker, (void *) (long long) 0);
    Pthread_create(&p2, NULL, worker, (void *) (long long) 1);
    Pthread_join(p1, NULL);
    Pthread_join(p2, NULL);
    return 0;
}
 |