客户端：：：：
#include <Winsock2.h>
 #include <stdio.h>



 void main()

 {

//加载套接字库

WORD wVersionRequested;

WSADATA wsaData;

int err;


wVersionRequested = MAKEWORD( 1, 1 );//请求一个1.1的版本的Winsocket库


err = WSAStartup( wVersionRequested, &wsaData );//1、加载套接字库，2、确定使用哪一个套接字的版本库

if ( err != 0 ) { 

return;

}



if ( LOBYTE( wsaData.wVersion ) != 1 ||

         HIBYTE( wsaData.wVersion ) != 1 ) {

WSACleanup( );//终止对weinsocket库的使用

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");//服务器端的IP地址，本地回路地址（一台），不管有没有网卡都可以，用于测试

     addrSrv.sin_family=AF_INET;

addrSrv.sin_port=htons(6000);

connect(sockClient,(SOCKADDR *)&addrSrv,sizeof(SOCKADDR));

char recvBuf[100];

recv(sockClient,recvBuf,100,0);

printf("%s\n",recvBuf);

send(sockClient,"This is zhangsan",strlen("This is zhangsan")+1,0);

closesocket(sockClient);

WSACleanup();



}
服务端：：：：：
#include <Winsock2.h>
 #include <stdio.h>


 void main()
 {
//加载套接字库
WORD wVersionRequested;
WSADATA wsaData;
int err;

wVersionRequested = MAKEWORD( 1, 1 );//请求一个1.1的版本的Winsocket库

err = WSAStartup( wVersionRequested, &wsaData );//1、加载套接字库，2、确定使用哪一个套接字的版本库
if ( err != 0 ) { 
return;
}


if ( LOBYTE( wsaData.wVersion ) != 1 ||
         HIBYTE( wsaData.wVersion ) != 1 ) {
WSACleanup( );//终止对weinsocket库的使用
return; 
}
//到此加载完库
 //创建套接字
     SOCKET sockSrv=socket(AF_INET,SOCK_STREAM,0);//服务器端的套接字
 //绑定套接字到地址和端口上
     SOCKADDR_IN addrSrv;
     addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY);//
/*htonl
        The htonl function converts a u_long from host to TCP/IP network byte order (which is big-endian).


        u_long htonl(
           u_long hostlong  );*/
     addrSrv.sin_family=AF_INET;
     addrSrv.sin_port=htons(6000);//只能用1024以上
bind(sockSrv,(SOCKADDR *)&addrSrv,sizeof(SOCKADDR));
     listen(sockSrv,5);
SOCKADDR_IN addrClient;
int len=sizeof(SOCKADDR);
while(1)
{
         SOCKET sockConn=accept(sockSrv,(SOCKADDR *)&addrClient,&len);
char sendBuf[100];
sprintf(sendBuf,"welcom %s to http://www.sunxin.org",inet_ntoa(addrClient.sin_addr));
send(sockConn,sendBuf,strlen(sendBuf)+1,0);
char recvBuf[100];
recv(sockConn,recvBuf,100,0);
printf("%s\n",recvBuf);
closesocket(sockConn);
}
 }注释：：进一步完善中...
intWSAStartup(WORD wVersionRequested, LPWSADATA lpWSAData);
wVersionRequested 
[in] Highest version of Windows Sockets support that the caller can use.The high-order byte specifies the minor version (revision) number; thelow-order byte specifies the major version number. 
lpWSAData 
[out] Pointer to the ​​WSADATA​​data structure that is to receive details of the Windows Socketsimplementation. 
 
typedef structWSAData {
  WORD                  wVersion;
  WORD                  wHighVersion;
  char                  szDescription[WSADESCRIPTION_LEN+1];
  char                 szSystemStatus[WSASYS_STATUS_LEN+1];
  unsigned short        iMaxSockets;
  unsigned short        iMaxUdpDg;
  char FAR *            lpVendorInfo;
} WSADATA,*LPWSADATA; 
Members
wVersion 
Version of the Windows Socketsspecification that the Ws2_32.dll expects the caller to use. 
wHighVersion
Highest version of the Windows Socketsspecification that this .dll can support (also encoded as above). Normally thisis the same as wVersion. 
szDescription 
Null-terminated ASCII string into which theWs2_32.dll copies a description of the Windows Sockets implementation. The text(up to 256 characters in length) can contain any characters except control andformatting characters: the most likely use that an application can put this tois to display it (possibly truncated) in a status message. 
szSystemStatus 
Null-terminated ASCII string into which theWSs2_32.dll copies relevant status or configuration information. The Ws2_32.dllshould use this parameter only if the information might be useful to the useror support staff: it should not be considered as an extension of the szDescriptionparameter. 
iMaxSockets 
Retained for backward compatibility, butshould be ignored for Windows Sockets version 2 and later, as no single valuecan be appropriate for all underlying service providers. 
iMaxUdpDg 
Ignored for Windows Sockets version 2 andonward. iMaxUdpDg is retained for compatibility with Windows Socketsspecification 1.1, but should not be used when developing new applications. Forthe actual maximum message size specific to a particular Windows Socketsservice provider and socket type, applications should use ​​ getsockopt​​to retrieve the value of option SO_MAX_MSG_SIZE after a socket has beencreated. 
lpVendorInfo
Ignored for Windows Sockets version 2 andonward. It is retained for compatibility with Windows Sockets specification1.1. Applications needing to access vendor-specific configuration informationshould use getsockopt to retrieve the value of option PVD_CONFIG.The definition of this value (if utilized) is beyond the scope of thisspecification. 
 
SOCKET socket(
 int af,       
 int type,     
 int protocol 
);
af 
[in] Address family specification. 指定地址族，对于TCP/IP协议的套接字，只能是AF_INET(PF_INET)
type 
[in] Type specification for the new socket.指定Stocket类型，对于1.1版本的Stocket，只支持两种类型，SOCK_STREAM指定产生流式套接字，SOCK_DGRAM产生数据报套接字 
protocol 
[in] Protocol to be used with the socket that is specific to theindicated address family. 
   与特定的地址家族相关的协议0 根据地址格式和套接字类别自动选择一个合适的协议
若调用成功，返回一个新的SOCKET数据类型的套接字描述符。若失败则返回INVALID_SOCKET,错误信息可以通过WSNGetLastError函数返回。
 
int bind(
 SOCKET s,                           
 const struct sockaddr FAR *name,    
 int namelen                        
);
Parameters
s 
[in] Descriptor identifying an unbound socket. 指定要绑定的套接字
name 
[in] Address to assign to the socket from the ​​SOCKADDR​​structure. 指定该套接字的本地地址信息，是指向sockaddr结构的指针变量，由于改地址结构是为所有地址家族准备的，这个结构可能随所用的网络协议不同而不同，所以要用第三个参数指定改地址结构的长度。
namelen 
[in] Length of the value in the name parameter. 
struct sockaddr {
 u_short    sa_family;指定改地址家族，必须设为AF_INET
 char       sa_data[14];表示要求一块内存分片区
};  
可以用下面结构替代 
struct sockaddr_in {
       short   sin_family;
       u_short sin_port;
       struct  in_addr sin_addr;
       char    sin_zero[8];
};