#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <semaphore.h>
#define THREAD_NUM 16
sem_t semaphore;
void* routine(void* args) {
printf("(%d) Waiting in the login queue\n", *(int*)args);
sem_wait(&semaphore);
printf("(%d) Logged in\n", *(int*)args);
sleep(rand() % 5 + 1);
printf("(%d) Logged out\n", *(int*)args);
sem_post(&semaphore);
free(args);
}
int main(int argc, char *argv[]) {
pthread_t th[THREAD_NUM];
sem_init(&semaphore, 0, 32);
int i;
for (i = 0; i < THREAD_NUM; i++) {
int* a = malloc(sizeof(int));
*a = i;
if (pthread_create(&th[i], NULL, &routine, a) != 0) {
perror("Failed to create thread");
}
}
for (i = 0; i < THREAD_NUM; i++) {
if (pthread_join(th[i], NULL) != 0) {
perror("Failed to join thread");
}
}
sem_destroy(&semaphore);
return 0;
}