/*****************************************************************************
* SOURCE: This is a translation of a Pthread program from the Lawrence Livermore
* Computing Center POSIX Threads Programming Exercise at:
* https://computing.llnl.gov/tutorials/pthreads/exercise.html
* FILE: detached.cvl
* DESCRIPTION:
*   This example demonstrates how to explicitly create a thread in a 
*   detached state. This might be done to conserve some system resources
*   if the thread never needs to join later. Compare with the join.cvl program
*   where the threads are created joinable.
* Command line execution:
* civl verify -inputNUM_THREADS=4 detached.cvl
******************************************************************************/
#include "pthread.cvh"
#include <civlc.h>
#include <stdio.h>
#include <stdlib.h>
#include "math.cvh"

$input int NUM_THREADS;

void *BusyWork(void *t)
{
   long i,tid;
   double result=0.0;
   tid = (long)*t;
   printf("Thread %d starting...\n",tid);
   for (i=0; i<1000000; i++) {
     result = result + sin(i) * tan(i);
     }
   printf("Thread %d done. Result = %e\n",tid, result);
   pthread_exit(NULL, false, NULL, 0);
}

int main(void)
{
pthread_t thread[NUM_THREADS];
pthread_attr_t attr;
int rc;
long t; 
long j[NUM_THREADS];

/* Initialize and set thread detached attribute */
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

for(t=0;t<NUM_THREADS;t++) {
   printf("Main: creating thread %d\n", t);
   j[t] = (long)t;
   rc = pthread_create(&thread[t], &attr, BusyWork, (void *)&j[t]); 
   if (rc) {
      $assert($false, "ERROR; return code from pthread_create() is %d", rc);
      return 0;
     }
  }

/* We're done with the attribute object, so we can destroy it */
pthread_attr_destroy(&attr);

/* The main thread is done, so we need to call pthread_exit explicitly to
*  permit the working threads to continue even after main completes.
*/
printf("Main: program completed. Exiting.\n");
pthread_exit(NULL, true, thread, NUM_THREADS);
}