fork_vs_thread

==============================================================================
C Code for fork() creation test
==============================================================================
#include <stdio.h>
#include <stdlib.h>

#define NFORKS 50000

void do_nothing() {
  int i;
  i= 0;
}

int main(int argc, char *argv[])
{
 
  int pid, j, status;

  for (j=0; j<NFORKS; j++) {

    /*** error handling ***/
    if ((pid = fork()) < 0 ) {
      printf ("fork failed with error code= %d\n", pid);
      exit(0);
    }
    /*** this is the child of the fork ***/
    else if (pid ==0) {
      do_nothing();
      exit(0);
    }

    /*** this is the parent of the fork ***/
    else {
      waitpid(pid, status, 0);
    }
  }
} 

==============================================================================
C Code for pthread_create() test
==============================================================================
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>

#define NTHREADS 50000

void *do_nothing(void *null) {
  int i;
  i=0;
  pthread_exit(NULL);
}                     

int main(int argc, char *argv[])
{

  int rc, i, j, detachstate;
  pthread_t tid;
  pthread_attr_t attr;

  pthread_attr_init(&attr);
  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);

  for (j=0; j<NTHREADS; j++) {
    rc = pthread_create(&tid, &attr, do_nothing, NULL);
    if (rc) {             
      printf("ERROR; return code from pthread_create() is %d\n", rc);
      exit(-1);
    }

    /* Wait for the thread */
    rc = pthread_join(tid, NULL);
    if (rc) {
      printf("ERROR; return code from pthread_join() is %d\n", rc);
      exit(-1);
    }
  }

  pthread_attr_destroy(&attr);
  pthread_exit(NULL);

}

 

https://computing.llnl.gov/tutorials/pthreads/fork_vs_thread.txt