基于TCP的socket编程
基于TCP的socket编程
sockets(套接字)编程有三种,流式套接字(SOCK_STREAM)TCP,数据报套接字UDP (SOCK_DGRAM),原始套接字(SOCK_RAW);基于TCP的socket编程是采用的流式套接字。
在这个程序中,将两个工程添加到一个工作区。要链接一个ws2_32.lib的库文件。
服务器端编程的步骤:
1:加载套接字库,创建套接字(WSAStartup()/socket());
2:绑定套接字到一个IP地址和一个端口上(bind());
3:将套接字设置为监听模式等待连接请求(listen());
4:请求到来后,接受连接请求,返回一个新的对应于此次连接的套接字(accept());
5:用返回的套接字和客户端进行通信(send()/recv());
6:返回,等待另一连接请求;
7:关闭套接字,关闭加载的套接字库(closesocket()/WSACleanup())。
以下是服务器端代码如下(VC项目应建立在windows控制台模式下的应用程序):
#include
#include
void main()
{
WORD wVersionRequested; //版本号
WSADATA wsaData; //启动SOCKET的
int err;
wVersionRequested = MAKEWORD( 1, 1 );//建立版本
err = WSAStartup( wVersionRequested, &wsaData );//启用socket
if ( err != 0 ) //如果返回值不等于0,那么表示出错,直截退出程序
{
return;
}
SOCKET sockSrv=socket(AF_INET,SOCK_STREAM,0); //设置为TCP流模式SOCKADDR_IN addrSrv; //
addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY); //INADDR_ANY为本机任意IP
addrSrv.sin_family=AF_INET; //
addrSrv.sin_port=htons(6000); //侦听端口为6000 bind(sockSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR)); //绑定到SOCKET
listen(sockSrv, 5); //侦听sockSrv,并设置最大客户连接数为5。SOCKADDR_IN addrClient;
int len=sizeof(SOCKADDR);
{
SOCKET sockConn=accept(sockSrv,(SOCKADDR*)&addrClient,&len); //等待客户连接,如果没有客户连接时,则此函数在这里会产生阻塞。
char sendBuf[50];
sprintf(sendBuf,"Welcome %s to here!",inet_ntoa(addrClient.sin_addr));
send(sockConn,sendBuf,strlen(sendBuf)+1,0); //发送sendBuf的字符串给客户端。char recvBuf[50];
recv(sockConn,recvBuf,50,0); //从客户端接收50个字节。printf("%s\n",recvBuf); //显示客户端发过来的字符串closesocket(sockConn); //关闭字
}
WSACleanup(); //清理
}
很简单吧?呵呵。再复杂的使用TCP协议的网络通信程序也是基于此的。下面顺便也把客户端的程序写出来。相同部分的程序就不不注释了。
客户端编程的步骤:
1:加载套接字库,创建套接字(WSAStartup()/socket());
2:向服务器发出连接请求(connect());
3:和服务器端进行通信(send()/recv());
4:关闭套接字,关闭加载的套接字库(closesocket()/WSACleanup())。
客户端的代码如下:
#include
#include
void main()
{
WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD( 1, 1 );
err = WSAStartup( wVersionRequested, &wsaData );
if ( err != 0 ) {
return;
}
SOCKET sockClient=socket(AF_INET,SOCK_STREAM,0);
SOCKADDR_IN addrSrv;
addrSrv.sin_addr.S_un.S_addr=inet_addr("127.0.0.1");//设置SOCKET的IP为本机。addrSrv.sin_family=AF_INET;
addrSrv.sin_port=htons(6000);//端口为6000,服务端和客户端的端口一定要相同.否则是连
connect(sockClient,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));//根据addrSrv连接服务端
char recvBuf[50];
recv(sockClient,recvBuf,50,0); //接收50字符
printf("%s\n",recvBuf); //显示
send(sockClient,"hello",strlen("hello")+1,0); //发送一个hello
closesocket(sockClient); //关闭
WSACleanup(); //清理
}
对了,在这种模式叫做什么同步阻塞模式,遇到连接,发送,接受函数时,程序便会等待,直到完成操作,才会执行下面的程序段,所以一般这些网络操作都会开启一个新线程去完成,那样不会使程序的主线程阻塞。
windows socket 编程实例--TCP
客户端向服务器发信息, 收到后打印一下,再回发. 客户端收到信息后打印.【来自网络】
---------------这是服务器的-------------------
#include "afxmt.h"
#include "winsock2.h"
#pragma comment(lib,"WS2_32.LIB")
int bufi;
class mserver{
private:
SOCKET ssock,csock;
sockaddr_in saddr,caddr;
int len;
char buf[4096];
public:
mserver(){
}
mserver(int port,int maxclient){
saddr.sin_family=AF_INET;
saddr.sin_port=htons(port);
saddr.sin_addr.s_addr=INADDR_ANY;
ssock=socket(AF_INET,SOCK_STREAM,0);
if(ssock==INVALID_SOCKET){
printf("build socket error\n");
}
if(bind(ssock,(struct sockaddr*)&saddr,sizeof(saddr))==SOCKET_ERROR){ printf("socket bind fail\n");
}
len=sizeof(caddr);
}
void close(){
closesocket(ssock);
closesocket(csock);
}
void beginlisten(){
if(listen(ssock,10)==SOCKET_ERROR){
printf("listen fail\n");
}
}
void maccept(){
sockaddr a;
csock=accept(ssock,(struct sockaddr*)&caddr,&len);
if(csock==INVALID_SOCKET){
printf("accept fail : %d\n",WSAGetLastError());
}
printf("client from %s connected\n",inet_ntoa(caddr.sin_addr));
}
int receive(){
memset(buf,0,4096);
if(recv(csock,buf,4096,0)==SOCKET_ERROR){
return 0;
}
printf("message received : %s\n",buf);
send(csock,buf,4096,0);
return 1;
}
};
int main()
{
WSADATA wsaData;
if (WSAStartup(MAKEWORD(2,1),&wsaData)){
printf("Winsock initializing fail\n");
WSACleanup();
return 0;
}
mserver s(12345,10);
s.beginlisten();
s.maccept();
while(s.receive());
s.close();
WSACleanup();
return 0;
}
----------------这是客户端的-------------------
#include "stdio.h"
#include "afxmt.h"
#include "winsock2.h"
#pragma comment(lib,"WS2_32.LIB")
class mclient{
private:
SOCKET sock;
sockaddr_in saddr;
int len;
char buf[4096];
public:
mclient(){
sock=socket(AF_INET,SOCK_STREAM,0);
len=sizeof(saddr);
}
bool mconnect(char* addr,int port){
saddr.sin_family=AF_INET;
saddr.sin_port=htons(port);
saddr.sin_addr.s_addr=inet_addr(addr);
if(connect(sock,(struct sockaddr*)&saddr,len)==SOCKET_ERROR){ printf("connect fail : %d",WSAGetLastError());
return false;
}
return true;
}
void close(){
closesocket(sock);
}
void msend(char* mes){
send(sock,mes,strlen(mes),0);
}
bool receive(){
memset(buf,0,4096);
if(recv(sock,buf,4096,0)==SOCKET_ERROR){
return false;
}
else{
printf("received from server : %s\n",buf);
return true;
}
}
};
int main()
{
WSADATA wsaData;
if (WSAStartup(MAKEWORD(2,1),&wsaData)){ printf("Winsock initializing fail\n");
WSACleanup();
return 0;
}
mclient a;
if(!a.mconnect("172.18.48.7",12345)){
return 0;
}
char buf[1024];
while(scanf("%s",buf)){
if(strcmp(buf,"quit")==0){
break;
}
a.msend(buf);
a.receive();
}
a.close();
WSACleanup();
return 0;
}
socket 编程——tcp简单实例
//服务器端代码
#include
#include
#pragma comment(lib,"ws2_32.lib")
{
WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD(1,1);
err = WSAStartup(wVersionRequested,&wsaData);
if(err != 0)
{
return ;
}
if(LOBYTE( wsaData.wVersion)!=1 ||
HIBYTE( wsaData.wVersion )!=1)
{
return;
}
SOCKET sockServer = socket(AF_INET,SOCK_STREAM,0);
SOCKADDR_IN addrServer;
addrServer.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
addrServer.sin_family = AF_INET;
addrServer.sin_port = htons(5555);
::bind(sockServer,(SOCKADDR*)&addrServer,sizeof(SOCKADDR));
listen(sockServer,5);
SOCKADDR_IN addrClient;
int len = sizeof(SOCKADDR);
while(1)
{
SOCKET sockConn = accept(sockServer,(SOCKADDR*)&addrClient,&len); char sendBuf[100];
sprintf(sendBuf,"Welcom %s to here!",inet_ntoa(addrClient.sin_addr)); send(sockConn,sendBuf,strlen(sendBuf)+1,0);
char recvBuf[100];
recv(sockConn,recvBuf,100,0);
printf("Client say: %s\n",recvBuf);
closesocket(sockConn);
}
}
//客户端代码,
#include
#include
#pragma comment(lib,"ws2_32.lib")
{
WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD(1,1);
err = WSAStartup(wVersionRequested,&wsaData);
if(err != 0){
return ;
}
if(LOBYTE( wsaData.wVersion) !=1 ||
HIBYTE( wsaData.wVersion ) !=1)
{
WSACleanup();
return;
}
SOCKET sockClient = socket(AF_INET,SOCK_STREAM,0);
SOCKADDR_IN addrServer;
addrServer.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
addrServer.sin_family = AF_INET;
addrServer.sin_port = htons(5555);
connect(sockClient,(SOCKADDR*)&addrServer,sizeof(SOCKADDR)); send(sockClient,"hello",strlen("hello")+1,0);
char recvBuf[100];
//sprintf(recvBuf,0,100);
recv(sockClient,recvBuf,100,0);
printf("%s\n",recvBuf);
closesocket(sockClient);
WSACleanup();
}