Easily async and resync any function, casts are automatically made. You can pass any number of arguments, and can get the return value. Easy interface for mutex.

easy-thread.c

#include <stdio.h>
#include <assert.h>
#include <pthread.h>
#include <stdarg.h>

#define thread_local _Thread_local

#ifndef THREAD_MAX
#define THREAD_MAX 50
#endif

#ifndef MUTEX_MAX
#define MUTEX_MAX 50
#endif

pthread_t t_id[THREAD_MAX] = {0};
pthread_mutex_t mutex_id[MUTEX_MAX] = {0};

size_t ThreadCount = 0;
size_t MutexCount = 0;

typedef pthread_t* thread;

#define FUNCTION void*
#define VARIABLE void*

thread async(FUNCTION function, ...) {}
#define async(x, ...) &t_id[ThreadCount]; { \
	void* thread(void *ignore) \
	{ \
		assert("THREAD MAX rechead!" && ThreadCount < THREAD_MAX); \
		x(__VA_ARGS__); \
	} \
		pthread_create(&t_id[ThreadCount++], NULL, thread, NULL); \
	}

thread asyncEx(VARIABLE var, FUNCTION function, ...) {}
#define asyncEx(var, x, ...) &t_id[ThreadCount]; { \
	void* thread(void *ignore) \
	{ \
		assert("THREAD MAX rechead!" && ThreadCount < THREAD_MAX); \
		var = x(__VA_ARGS__); \
	} \
		pthread_create(&t_id[ThreadCount++], NULL, thread, NULL); \
	}

#undef VARIABLE
#undef FUNCTION

void resync(thread id) {}
#define resync(x) pthread_join(*x, NULL)

#define MACRO void

MACRO thread_lock(int id) {}
#define thread_lock(id) \
	assert("MUTEX MAX rechead!" && MutexCount < MUTEX_MAX); \
	if (mutex_id[id] == 0) mutex_id[id] = PTHREAD_MUTEX_INITIALIZER; \
	pthread_mutex_lock(&(mutex_id[id]))

MACRO thread_unlock(int id) {}
#define thread_unlock(id) pthread_mutex_unlock(&mutex_id[id])

#undef MACRO

/*///////////////////////////////////
	
		Testing:
		
///////////////////////////////////*/

void foo(int count, ...) {
	va_list args;
	va_start(args, count);
	
	while (count--) {
		int i = va_arg(args, int);
		printf("%i ", i);
	}
	printf("\n\n");
}

int bar(char* msg, int n) {
	int i;	
	for (i=0; i<n; i++)
		printf("%s\n", msg);
		
	return n * 2;
}

int main() {
	thread t1 = async(foo, 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);	
	thread t2 = async(bar, "foo!", 5);
	
	int i;
	thread t3 = asyncEx(i, bar, "bar!", 5);
	
	resync(t1);	
	resync(t2);
	resync(t3);
	
	printf("returned value: %i\n", i);
}