sockets(套接字)编程有三种,流式套接字(SOCK_STREAM),数据报套接字(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(SOCK_STREAM)。基于UDP采用的数据报套接字(SOCK_DGRAM).1.TCP流式套接字的编程步骤在使用之前须链接库函数:工程->属性->连接器->输入->附加依赖项.ws2_32.lib,OK!服务器端程序:1、加载套接字库2、创建套接字(socket)。 3、将套接字绑定到一个本地地址和端口上(bind)。4、将套接字设为监听模式,准备接收客户请求(listen)。5、等待客户请求到来;当请求到来后,接受连接请求,返回一个新的对应于此次连接的套接字(accept)。6、用返回的套接字和客户端进行通信(send/recv)。7、返回,等待另一客户请求。8、关闭套接字。客户端程序:1、加载套接字库2、创建套接字(socket)。 3、向服务器发出连接请求(connect)。4、和服务器端进行通信(send/recv)。5、关闭套接字。服务器端代码如下:#include <Winsock2.h>//加裁头文件#include <stdio.h>//加载标准输入输出头文件
void main(){WORD wVersionRequested;//版本号WSADATA wsaData;int err;
wVersionRequested = MAKEWORD( 1, 1 );//1.1版本的套接字
err = WSAStartup( wVersionRequested, &wsaData );if ( err != 0 ) {return;}//加载套接字库,加裁失败则返回
if ( LOBYTE( wsaData.wVersion ) != 1 || HIBYTE( wsaData.wVersion ) != 1 ) {WSACleanup( );return; }//如果不是1.1的则退出SOCKET sockSrv=socket(AF_INET,SOCK_STREAM,0);//创建套接字(socket)。
SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY);//转换Unsigned short为网络字节序的格式addrSrv.sin_family=AF_INET;addrSrv.sin_port=htons(6000);
bind(sockSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));//将套接字绑定到一个本地地址和端口上(bind)listen(sockSrv,5);//将套接字设为监听模式,准备接收客户请求(listen)。
SOCKADDR_IN addrClient;//定义地址族int len=sizeof(SOCKADDR);//初始化这个参数,这个参数必须被初始化
while(1){SOCKET sockConn=accept(sockSrv,(SOCKADDR*)&addrClient,&len);accept的第三个参数一定要有初始值。//等待客户请求到来;当请求到来后,接受连接请求,返回一个新的对应于此次连接的套接字(accept)。//此时程序在此发生阻塞char sendBuf[100];sprintf(sendBuf,"Welcome %s to http://www.sunxin.org", inet_ntoa(addrClient.sin_addr));//用返回的套接字和客户端进行通信(send/recv)。send(sockConn,sendBuf,strlen(sendBuf)+1,0);char recvBuf[100];recv(sockConn,recvBuf,100,0);printf("%s/n",recvBuf);closesocket(sockConn);//关闭套接字。等待另一个用户请求}}
客户端代码如下:#include <Winsock2.h>#include <stdio.h>
void main(){WORD wVersionRequested;WSADATA wsaData;int err;
wVersionRequested = MAKEWORD( 1, 1 );
err = WSAStartup( wVersionRequested, &wsaData );加载套接字库if ( err != 0 ) {return;}
if ( LOBYTE( wsaData.wVersion ) != 1 || HIBYTE( wsaData.wVersion ) != 1 ) {WSACleanup( );return; }SOCKET sockClient=socket(AF_INET,SOCK_STREAM,0);创建套接字(socket)。
SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr=inet_addr("127.0.0.1");addrSrv.sin_family=AF_INET;addrSrv.sin_port=htons(6000);connect(sockClient,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));向服务器发出连接请求(connect)。
char recvBuf[100];和服务器端进行通信(send/recv)。recv(sockClient,recvBuf,100,0);printf("%s/n",recvBuf);send(sockClient,"This is lisi",strlen("This is lisi")+1,0);
closesocket(sockClient);关闭套接字。WSACleanup();//必须调用这个函数清除参数}
2.UDP型套接字。服务器端(接收端)程序:1、创建套接字(socket)。 2、将套接字绑定到一个本地地址和端口上(bind)。3、等待接收数据(recvfrom)。4、关闭套接字。客户端(发送端)程序:1、创建套接字(socket)。 2、向服务器发送数据(sendto)。3、关闭套接字。服务器端代码:#include <Winsock2.h>#include <stdio.h>
void main(){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 sockSrv=socket(AF_INET,SOCK_DGRAM,0);SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY);addrSrv.sin_family=AF_INET;addrSrv.sin_port=htons(6000);
bind(sockSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));
SOCKADDR_IN addrClient;int len=sizeof(SOCKADDR);char recvBuf[100];
recvfrom(sockSrv,recvBuf,100,0,(SOCKADDR*)&addrClient,&len);printf("%s/n",recvBuf);closesocket(sockSrv);WSACleanup();}
客户端代码:#include <Winsock2.h>#include <stdio.h>
void main(){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_DGRAM,0);SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr=inet_addr("127.0.0.1");addrSrv.sin_family=AF_INET;addrSrv.sin_port=htons(6000);
sendto(sockClient,"Hello",strlen("Hello")+1,0,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));closesocket(sockClient);WSACleanup();}===========下面是字符界面下的一个简单UDP聊天程序=====服务器端:==============================#include <stdio.h>#include <WINSOCK2.H>
void main(){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 sockSrv=socket(AF_INET,SOCK_DGRAM,0);
SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY);addrSrv.sin_family=AF_INET;addrSrv.sin_port=htons(6101);
bind(sockSrv,(sockaddr*)&addrSrv,sizeof(sockaddr));
char sendBuf[100];char recvBuf[100];char tempBuf[100];int len=sizeof(sockaddr); SOCKADDR_IN addrClient;while(1){recvfrom(sockSrv,tempBuf,strlen(tempBuf),0,(sockaddr*)&addrClient,&len);if('q'!=tempBuf[0]){ sprintf(recvBuf,"%s say: %s",inet_ntoa(addrClient.sin_addr),tempBuf); printf("%s/n",recvBuf); printf("please input your data: "); gets(sendBuf); sendto(sockSrv,sendBuf,strlen(sendBuf)+1,0,(sockaddr*)&addrClient,len);}else{ printf("%s request to quit the chat platform./n", inet_ntoa(addrClient.sin_addr)); sendto(sockSrv,"q",strlen("q")+1,0,(sockaddr*)&addrClient,len); break;}}closesocket(sockSrv); WSACleanup();
}
客户端:===============================#include <stdio.h>#include <WINSOCK2.H>
void main(){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_DGRAM,0);
SOCKADDR_IN addrSrv;addrSrv.sin_addr.S_un.S_addr=inet_addr("127.0.0.1");//htonl htons inet_addr inet_ntoaaddrSrv.sin_family=AF_INET;addrSrv.sin_port=htons(6101);
char sendBuf[100];char tempBuf[100];char recvBuf[100];int len=sizeof(sockaddr);
while(1){printf("please input your data: ");gets(sendBuf);sendto(sockClient,sendBuf,strlen(sendBuf)+1,0,(sockaddr*)&addrSrv,len);recvfrom(sockClient,tempBuf,strlen(tempBuf),0,(sockaddr*)&addrSrv,&len);if('q'!=tempBuf[0]){ sprintf(recvBuf,"%s say: %s",inet_ntoa(addrSrv.sin_addr),tempBuf); printf("%s/n",recvBuf);}else{ printf("the server has been closed!/n"); sendto(sockClient,"q",strlen("q")+1,0,(sockaddr*)&addrSrv,len); break;}
}
closesocket(sockClient);WSACleanup();