第四章主要的代码是，实现迭代回声服务器端和客户端
echo_server_win.cpp
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <WinSock2.h>#define BUF_SZIE 1024
void ErrorHandling(char *message);int main(int argc, char *argv[]) {WSADATA wsaData;SOCKET hServSock, hClntSock;char message[BUF_SZIE];int strlen, i;SOCKADDR_IN servAdr, clntAdr;int clntAdrSize;if (argc != 2) {printf("Usage : %s <port>\n", argv[0]);exit(1);}if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)ErrorHandling("WSAStartup() error!");hServSock = socket(PF_INET, SOCK_STREAM, 0);if (hServSock == INVALID_SOCKET)ErrorHandling("socket() error!");memset(&servAdr, 0, sizeof(servAdr));servAdr.sin_family = AF_INET;servAdr.sin_addr.s_addr = htonl(INADDR_ANY);servAdr.sin_port = htons(atoi(argv[1]));if (bind(hServSock, (SOCKADDR *)&servAdr, sizeof(servAdr)) == SOCKET_ERROR)ErrorHandling("bind() error!");if (listen(hServSock, 5) == SOCKET_ERROR)ErrorHandling("listen() error!");clntAdrSize = sizeof(clntAdr);for (i = 0; i < 5; i++) {hClntSock = accept(hServSock, (SOCKADDR*)&clntAdr, &clntAdrSize);if (hClntSock == -1)ErrorHandling("accept error!");elseprintf("Connected client %d \n", i + 1);while ((strlen = recv(hClntSock, message, BUF_SZIE, 0) )!= 0)send(hClntSock, message, strlen, 0);closesocket(hClntSock);}closesocket(hServSock);WSACleanup();return 0;
}void ErrorHandling(char *message) {fputs(message, stderr);fputs("\n", stderr);exit(1);
}
echo_client_win.cpp
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <WinSock2.h>#define BUF_SIZE 1024
void ErrorHandling(char* message);int main(int argc, char * argv[]) {WSADATA wsaData;SOCKET hSocket;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!");hSocket = socket(PF_INET, SOCK_STREAM, 0);if (hSocket == INVALID_SOCKET)ErrorHandling("socket() error!");memset(&servAdr, 0, sizeof(servAdr));servAdr.sin_family = AF_INET;servAdr.sin_addr.s_addr = inet_addr(argv[1]);servAdr.sin_port = htons(atoi(argv[2]));if (connect(hSocket, (SOCKADDR*)&servAdr, sizeof(servAdr)) == SOCKET_ERROR)ErrorHandling("connect() error!");elseputs("Connected......");while (1) {fputs("Inputs message(Q to quit): ",stdout);fgets(message, BUF_SIZE, stdin);if (!strcmp(message, "q\n") || !strcmp(message, "Q\n"))break;send(hSocket, message, strlen(message), 0);strLen = recv(hSocket, message, BUF_SIZE - 1, 0);message[strLen] = 0;printf("Message from server: %s", message);}closesocket(hSocket);WSACleanup();return 0;
}void ErrorHandling(char * message) {fputs(message, stderr);fputc('\n', stderr);exit(1);
}