linux 多線程用信號量進行同步例子

#include #include #include #include #include void *thread_function(void *arg); sem_t bin_sem; #define WORK_SIZE 1024 char work_area[WORK_SIZE]; int main() { int res; pthread_t a_thread; void *thread_result; res = sem_init(&bin_sem, 0, 0); if (res != 0) { perror("Semaphore initialization failed"); exit(EXIT_FAILURE); } res = pthread_create(&a_thread, NULL, thread_function, NULL); if (res != 0) { perror("Thread creation failed"); exit(EXIT_FAILURE); } printf("Input some text. Enter 'end' to finish/n"); while(strncmp("end", work_area, 3) != 0) { fgets(work_area, WORK_SIZE, stdin); sem_post(&bin_sem); } printf("/nWaiting for thread to finish.../n"); res = pthread_join(a_thread, &thread_result); if (res != 0) { perror("Thread join failed"); exit(EXIT_FAILURE); } printf("Thread joined/n"); sem_destroy(&bin_sem); exit(EXIT_SUCCESS); } void *thread_function(void *arg) { sem_wait(&bin_sem); while(strncmp("end", work_area, 3) != 0) { printf("You input %d characters/n", strlen(work_area) -1); sem_wait(&bin_sem); } pthread_exit(NULL); }