// This UDP Server will take command argument as port number, and
// when a clients datagram comes in, the server displays this message
// with clients ip address, and the server bounces back the message
// with servers name
#pragma comment(lib, "ws2_32.lib")
#include <WinSock2.h>
#include <stdio.h>


int main(int argc, char** argv) {
	if (argc != 2) {
		printf("Usage: %s [port number]\n", argv[0]);
		return 1;
	}
	WSADATA wsa;
	int ret = WSAStartup(MAKEWORD(2, 2), &wsa);
	if (ret) {
		printf("WinSock API is not ready!\n");
		return 1;
	}
	printf("WinSock API is ready!\n");
	// we now can use socket functions
	SOCKET serv = socket(AF_INET, SOCK_DGRAM, 0);
	if (serv == INVALID_SOCKET) {
		printf("Socket cannot be created\n");
		return 1;
	}
	printf("Socket is ready!\n");
	SOCKADDR_IN myaddr;
	myaddr.sin_family = AF_INET;
	myaddr.sin_addr.s_addr = htonl(INADDR_ANY);
	myaddr.sin_port = htons(atoi(argv[1]));
	ret = bind(serv, (SOCKADDR *)&myaddr, sizeof(myaddr));
	if (ret == SOCKET_ERROR) {
		printf("bind is FAILED\n");
		return 1;
	}
	printf("Bind is OK\n");
	while (1);
	WSACleanup();
	return 0;
}