queue.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <pthread.h>
#include <unistd.h>
#include <sys/types.h>

#define NUM_THREADS 8
#define PRINT_TIME

struct thread_data_t{
	int thread_id;
};

void * say_hello(void * args){
	struct thread_data_t * data = (struct thread_data_t *) args;
	int thread_id = data->thread_id;

	printf("Thread %d says hello!\n", thread_id);

	return NULL;
}

int main(void){
	pthread_t threads[NUM_THREADS];
	struct thread_data_t thread_data[NUM_THREADS];

	/* ---------- Start timing ---------- */
	time_t start = time(NULL);

	/* ---------- Create and run threads ---------- */
	int i;
	for(i = 0; i < NUM_THREADS; i++){
		thread_data[i].thread_id = i;
		pthread_create(&threads[i], NULL, &say_hello, &thread_data[i]);
	}

	/* ---------- Wait for threads to finish ---------- */
	for(i = 0; i < NUM_THREADS; i++){
		pthread_join(threads[i], NULL);
	}

	/* ---------- Finish timing ---------- */
	time_t end = time(NULL);

	/* ---------- Print time ---------- */
	#ifdef PRINT_TIME
		printf("\nTime: %ld\n", end - start);
	#endif

	return 0;
}