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

pthread_cond_t cond;
pthread_mutex_t mutex;

void *thread_func1(void* arg){
  printf("thread1 started\n");
  printf("thread1: signalling\n");
  pthread_cond_signal(&cond);
  printf("thread1: signalled\n");
  printf("thread1: exiting\n");
  pthread_exit(0);
}

void *thread_func2(void* arg){
  printf("thread2 started\n");
  printf("thread2: waiting for signal..\n");
  pthread_cond_wait(&cond, &mutex);
  printf("thread2: signal received\n");
  printf("thread2: exiting\n");
  pthread_exit(0);
}

int main(int argc, char** argv){
  pthread_t thread1, thread2;

  pthread_create(&thread1, NULL, thread_func1, NULL);
  pthread_create(&thread2, NULL, thread_func2, NULL);

  pthread_join(thread1, 0);
  pthread_join(thread2, 0);
  return 0;
}