1 2 #include <pthread.h> 3 #include <stdio.h> 4 #include <stdlib.h> 5 #include <unistd.h> 6 7 /* Test of the mechanism for showing all locks held by a thread -- one 8 thread has a lock, the other doesn't. Running w/ command line args 9 switches the has/has-not thread around, so as to test lockset 10 retention in both the history mechanism and the primary errors. */ 11 12 pthread_mutex_t mx = PTHREAD_MUTEX_INITIALIZER; 13 14 int x = 0; 15 16 void* child_fn ( void* arg ) 17 { 18 if (arg) pthread_mutex_lock(&mx); 19 x = 1; 20 if (arg) pthread_mutex_unlock(&mx); 21 return NULL; 22 } 23 24 int main ( int argc, char** argv ) 25 { 26 int sw = argc > 1; 27 pthread_t child1, child2; 28 29 if (pthread_create(&child1, NULL, child_fn, (void*)(long)(sw ? 0 : 1))) { 30 perror("pthread_create1"); 31 exit(1); 32 } 33 sleep(1); /* ensure repeatable results */ 34 if (pthread_create(&child2, NULL, child_fn, (void*)(long)(sw ? 1 : 0))) { 35 perror("pthread_create1"); 36 exit(1); 37 } 38 39 if (pthread_join(child1, NULL)) { 40 perror("pthread join1"); 41 exit(1); 42 } 43 44 if (pthread_join(child2, NULL)) { 45 perror("pthread join2"); 46 exit(1); 47 } 48 49 return 0; 50 } 51
