#include <pthread.h> 
#include <stdlib.h> 
  
#define NUM_THREADS     5

static pthread_mutex_t func_mutex = PTHREAD_MUTEX_INITIALIZER; 
 
void func() { 
    pthread_mutex_lock(&func_mutex); 
 
    // Do something that's not thread-safe. 
 
    pthread_mutex_unlock(&func_mutex); 
} 

void* worker(void* arg) { 
    int value = *((int*) arg); 
  
    // More business logic. 
  
    return 0; 
} 

int main(int argc, char** argv) { 
    pthread_t threads[NUM_THREADS]; 
    int thread_args[NUM_THREADS]; 
    int result_code; 
    
    for (unsigned int i = 0; i < NUM_THREADS; ++i) { 
        thread_args[i] = i; 
        result_code = pthread_create(&threads[i], 0, worker, (void*) &thread_args[i]); 
    } 
	for (int i = 0; i < NUM_THREADS; ++i) { 
        result_code = pthread_join(threads[i], 0); 
    } 

    exit(0); 
}