/* Demonstrate Thread Creating and Exiting */
/* Demonstrate use of condition variable   */
/* George F. Riley.  ECE3055, Spring 2003  */

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

#define N_THREAD 5

/* Mutex and condition variable for exit notification */
pthread_mutex_t DoneMutex;
pthread_cond_t  DoneCond;
int             DoneCount;
void* Philosopher ( int IntIndex )
{
 printf("Hello from Philosopher %d\n", IntIndex);
 pthread_mutex_lock(&DoneMutex);
 DoneCount++;
 if (DoneCount == N_THREAD)
   {
     pthread_cond_signal(&DoneCond); // Signal to main that all are done
   }
 pthread_mutex_unlock(&DoneMutex);
 printf("Exit  from Philosopher %d\n", IntIndex);
 return ((void*)IntIndex);
}

int main(int argc, char** argv)
{
int i;
pthread_t t[N_THREAD];

 pthread_mutex_init(&DoneMutex, NULL);
 pthread_cond_init(&DoneCond, NULL);

 /* This is important! */
 pthread_mutex_lock(&DoneMutex);
 /* Why did we lock this BEFORE thread creation? */

 for (i = 0; i < N_THREAD; i++)
   {
     printf("Creating thread %d\n", i);
     pthread_create(&t[i], NULL, 
           (void*(*)(void*))Philosopher, (void*)i);
     pthread_detach(t[i]);
   }
 pthread_cond_wait(&DoneCond, &DoneMutex);
 printf("Got condition signal\n");
 pthread_mutex_unlock(&DoneMutex);
 return (0);
}
#ifdef HERES_THE_OUTPUT
Creating thread 0
Creating thread 1
Creating thread 2
Creating thread 3
Hello from Philosopher 0
Hello from Philosopher 1
Hello from Philosopher 2
Creating thread 4
Hello from Philosopher 3
Hello from Philosopher 4
Exit  from Philosopher 0
Exit  from Philosopher 1
Exit  from Philosopher 2
Exit  from Philosopher 3
Got condition signal
Exit  from Philosopher 4
#endif