基于Windows的迭代回声服务器端/客户端(基于UDP的服务器端/客户端)

注意：博主用的visual studio 2015,在windows调试程序需要链接ws2_32.lib库，才能正常运行程序。

打开项目的“Property”->"Linker"->"Input"->"Additional Dependencies"，或者你也可以通过快捷键Alt+F7打开Property页面. 不知如何操作，可以看  http://blog.csdn.net/qq_16542775/article/details/51203465.

这里只贴出代码（操作方法和（基于TCP的服务器端/客户端方法相同！））：

uecho_server_win.c

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<WinSock2.h>
#define BUF_SIZE 30

void ErrorHandling(char *message);
int main(int argc, char *argv[]) {
	WSADATA wsaData;
	SOCKET servSock;
	char message[BUF_SIZE];
	int strLen;
	int clntAdrSz;

	SOCKADDR_IN servAdr, clntAdr;
	if (argc != 2) {
		printf("Usage : %s<port>\n", argv[0]);
		exit(1);
	}

	if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) 
		ErrorHandling("WSAStartup() error!");

	servSock = socket(PF_INET, SOCK_DGRAM, 0);
	if (servSock == INVALID_SOCKET)
		ErrorHandling("UDP socket creation error!");
	
	memset(&servAdr, 0, sizeof(servAdr));
	servAdr.sin_family = AF_INET;
	servAdr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
	servAdr.sin_port = htons(atoi(argv[1]));

	if (bind(servSock, (SOCKADDR*)&servAdr, sizeof(servAdr)) == SOCKET_ERROR)
		ErrorHandling("bind() error!");

	while (1) {
		clntAdrSz = sizeof(clntAdr);
		strLen = recvfrom(servSock, message, BUF_SIZE, 0, (SOCKADDR*)&clntAdr,&clntAdrSz);
		sendto(servSock, message, strLen, 0, (SOCKADDR*)&clntAdr, sizeof(clntAdr));
	}

	close(servSock);
	WSACleanup();
	return 0;
}

void ErrorHandling(char *message) {
	fputs(message, stderr);
	fputc('\n', stderr);
	exit(1);
}

uecho_client_win.c

#define _WINSOCK_DEPRECATED_NO_WARNINGS

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<WinSock2.h>

#define BUF_SIZE 30
void ErrorHandling(char *message);
int main(int argc, char *argv[]) {
	WSADATA wsaData;
	SOCKET sock;
	char message[BUF_SIZE];
	int strLen;

	SOCKADDR_IN servAdr;
	if (argc != 3) {
		printf("Usage: %s <IP><port>\n", argv[0]);
		exit(1);
	}

	if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
		ErrorHandling("WSAStartup() error!");
	sock = socket(PF_INET, SOCK_DGRAM, 0);
	if (sock == INVALID_SOCKET)
		ErrorHandling("socket() error!");

	memset(&servAdr, 0, sizeof(servAdr));
	servAdr.sin_family = AF_INET;
	servAdr.sin_addr.S_un.S_addr = inet_addr(argv[1]);
	servAdr.sin_port = htons(atoi(argv[2]));

	connect(sock, (SOCKADDR*)&servAdr, sizeof(servAdr));

	while (1) {
		fputs("Insert message(q to quit): ", stdout);
		fgets(message, sizeof(message), stdin);
		if (!strcmp(message, "q\n") || !strcmp(message, "Q\n"))
			break;

		send(sock, message,strlen(message), 0);
		strLen = recv(sock, message, sizeof(message) - 1, 0);
		message[strLen] = 0;
		printf("Message from server: %s", message);
	}

	closesocket(sock);
	WSACleanup();
	return 0;
}

void ErrorHandling(char *message) {
	fputs(message, stderr);
	fputc('\n', stderr);
}