#include <pthread.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include "prtastr.h"
#define BUFFSIZE 1024
static pthread_mutex_t join_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t  join_cond  = PTHREAD_COND_INITIALIZER;
static int delay = 0;
void *join_thread_main(void *arg){
  char buff[BUFFSIZE];
  sprintf(buff,"I'm the spawned thread chug chug chugging along\n");
  prtastr(buff, STDERR_FILENO, delay);
  pthread_mutex_lock(&join_mutex);
  pthread_cond_signal(&join_cond);
  pthread_mutex_unlock(&join_mutex);
  pthread_exit(NULL);
}
int main(int argc,  char *argv[]){
  pthread_t join_thread;
  if((argc != 2) ||
     ((delay = atoi(argv[1]))  < 0)) {
    fprintf (stderr, "Usage: %s delay\n", argv[0]);
    exit(EXIT_FAILURE); }
  fprintf(stderr, "main thread spawning thread\n");
  pthread_mutex_lock(&join_mutex);
  pthread_create(&join_thread,NULL,join_thread_main,NULL);
  fprintf(stderr, "main thread waiting\n");
  pthread_cond_wait(&join_cond, &join_mutex);
  fprintf(stderr, "main thread awoken\n");
  pthread_mutex_unlock(&join_mutex);
  exit(EXIT_SUCCESS);
}