TCPServer TCPClient三次握手模拟编程

套接字创建和关闭：

SOCKET socket(int af,int type,int protocal);



套接字类型：



SOCK_STREAM 流套接字，TCP提供有连接的可靠传输



SOCK_DGRAM 数据包套接字，UDP提供无连接的不可靠传输



SOCK_RAW 原始套接字

绑定套接字到指定的IP地址和端口号

int bind(

SOCKET s,//套接字句柄

const struct sockaddr * name,//关联的本地地址

int namelen//地址的长度

);

监听

int listen(

SOCKET s,//套接字

int backlog//最大连接数

)

连接

int accept(

SOCKET s,

struct sockaddr* addr,//取得对方的地址信息

int* addrlen//指向地址长度

);



int connect(

  SOCKET s,

  const struct sockaddr FAR* name,//连接的地址信息

  int namelen  //结构长度

);

收发数据

int send(

SOCKET s,

const char FAR* buf,//要发送数据的缓冲区地址

int len,//缓冲区长度

int flags//指定调用方式，通常为0

);

int recv(

SOCKET s,

char FAR* buf,

int len,

int

);

 

TCPSERVER端代码：

 1 // TCP.cpp : 定义控制台应用程序的入口点。

 2 //

 3 

 4 #include "stdafx.h"

 5 #include <winsock2.h>

 6 #include <stdio.h>

 7 

 8 #pragma comment(lib,"WS2_32")

 9 class CInitSock

10 {

11 public:

12     CInitSock(BYTE minorVer=2,BYTE majorVer=2)

13     {

14         WSADATA wsaData;

15         WORD sockVersion = MAKEWORD(minorVer,majorVer);

16         if(::WSAStartup(sockVersion,&wsaData)!=0)

17         {

18             exit(0);

19         }

20     }

21     ~CInitSock()

22     {

23         ::WSACleanup();

24     }

25 };

26 CInitSock initSock;

27 int _tmain(int argc, _TCHAR* argv[])

28 {

29     SOCKET sListen = ::socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

30     if(sListen == INVALID_SOCKET)

31     {

32         printf("Failed socket()\n");

33         return 0;

34     }

35     //填充sockaddr_in结构

36     sockaddr_in sin;

37     sin.sin_family = AF_INET;

38     sin.sin_port = htons(4567);

39     sin.sin_addr.S_un.S_addr = INADDR_ANY;

40     //绑定这个套接字的一个本地地址

41     if(::bind(sListen,(LPSOCKADDR)&sin,sizeof(sin)) == SOCKET_ERROR)

42     {

43         printf("Failed bind()\n");

44         return 0;

45     }

46     //进入监听模式

47     if(::listen(sListen,2) == SOCKET_ERROR)

48     {

49         printf("Failed listen()\n");

50         return 0;

51     }

52     //循环接受客户的连接请求

53     sockaddr_in remoteAddr;

54     int nAddrLen = sizeof(remoteAddr);

55     SOCKET sClient;

56     char szText[] = "TCP Server Demo!\r\n";

57     while(TRUE)

58     {

59         //接受新连接

60         sClient=::accept(sListen,(SOCKADDR*)&remoteAddr,&nAddrLen);

61         if(sClient == INVALID_SOCKET)

62         {

63             printf("Failed accept()");

64             continue;

65         }

66         printf("接受到一个连接：%s\r\n",inet_ntoa(remoteAddr.sin_addr));

67         //向客户端发送数据

68         ::send(sClient,szText,strlen(szText),0);

69         //关闭同客户端的连接

70         ::closesocket(sClient);

71     }

72     ::closesocket(sListen);

73     return 0;

74 }

TCPClient 端代码：

 1 // TCPClient.cpp : 定义控制台应用程序的入口点。

 2 //

 3 

 4 #include "stdafx.h"

 5 #include <winsock2.h>

 6 #include <stdio.h>

 7 #pragma comment(lib,"WS2_32")

 8 class CInitSock

 9 {

10 public:

11     CInitSock(BYTE minorVer=2,BYTE majorVer=2)

12     {

13         WSADATA wsaData;

14         WORD sockVersion = MAKEWORD(minorVer,majorVer);

15         if(::WSAStartup(sockVersion,&wsaData)!=0)

16         {

17             exit(0);

18         }

19     }

20     ~CInitSock()

21     {

22         ::WSACleanup();

23     }

24 };

25 CInitSock initSock;

26 

27 int _tmain(int argc, _TCHAR* argv[])

28 {

29     SOCKET s= ::socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

30     if(s==INVALID_SOCKET)

31     {

32         printf("Failed socket()\n");

33         return 0;

34     }

35     sockaddr_in servAddr;

36     servAddr.sin_family=AF_INET;

37     servAddr.sin_port=htons(4567);

38     servAddr.sin_addr.S_un.S_addr=inet_addr("49.140.16.244");

39     if(::connect(s,(sockaddr*)&servAddr,sizeof(servAddr))==-1)

40     {

41         printf("Failed connect()\n");

42         return 0;

43     }

44     //接受数据

45     char buff[256];

46     int nRecv=::recv(s,buff,256,0);

47     if(nRecv>0)

48     {

49         buff[nRecv] = '\0';

50         printf("接受到数据：%s",buff);

51     }

52     ::closesocket(s);

53     return 0;

54 }

结果：