multi thread (maybe processor) in c

cpus

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

int main() {
	long cpu_online = -1;
	long cpu_max = -1;
		
	#ifdef _SC_NPROCESSORS_ONLN
	
		cpu_online = sysconf(_SC_NPROCESSORS_ONLN);
		if (cpu_online < 1)
		{
			fprintf(stderr, "hmm somethings wrong! debug:cpu_online");
			return 1;
		}
		
		cpu_max = sysconf(_SC_NPROCESSORS_CONF);
		if (cpu_max < 1)
		{
			fprintf(stderr, "hmm somethings wrong! debug:cpu_max");
			return 1;
		}
		
		printf ("%ld of %ld processors online\n", cpu_online, cpu_max);
		
		return main_threaded(cpu_online);
		
	#else
		fprintf(stderr, "hmm somethings wrong!");
		return 1;
	#endif
}

typedef struct {
  
  int thread_id;
  pthread_t thread;
  
} workerStruct;

void *worker(void *param)
{
	workerStruct *me = (workerStruct *) param;
	
	printf("worker #%d started! \n", me->thread_id);
	
	int i = 0;
	while(1) i++;
	
	return NULL;

}

int main_threaded(max_worker){
	
	// test half processors
	// max_worker = max_worker / 2;
	
	int i = 0;
	
	workerStruct workers[4];
	
	for(; i < max_worker; i++){
		workers[i].thread_id = i;
		
		pthread_create(&workers[i].thread, NULL, worker, &workers[i]);
	}
	
	for(i = 0; i < max_worker; i++){
		pthread_join(workers[i].thread, NULL);
	}
	
	return 0;
}