socket通信的基本流程

1.面向连接的服务器：

#include <winsock.h>
#pragma comment(lib,"wsock32.lib")
int main(int argc, char* argv[])
{
SOCKET s,newsock;
sockaddr_in ser_addr;
sockaddr_in remote_addr;
int len;
char buf[128];
WSAData wsa;

WSAStartup(0x101,&wsa);
s = socket(AF_INET,SOCK_STREAM,0);
ser_addr.sin_family = AF_INET;
ser_addr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
ser_addr.sin_port = htons(0x1234);

bind(s,(sockaddr*)&ser_addr,sizeof(ser_addr));

listen(s,0);
while(1){
len = sizeof(remote_addr);
newsock = accept(s,(sockaddr*)&remote_addr,&len);
recv(newsock,buf,sizeof(buf),0);
send(newsock,"ACK",3,0);
closesocket(newsock);
}
closesocket(s);
WSACleanup();
return 0;
}

2.面向连接的客户机：

#include <winsock.h>
#pragma comment(lib,"wsock32.lib")
int main(int argc, char* argv[])
{
SOCKET s;
sockaddr_in local,server;
WSAData wsa;
char *buf = "I am a client";
char recvbuf[128];

WSAStartup(0x101,&wsa);

s = socket(AF_INET,SOCK_STREAM,0);
local.sin_family = AF_INET;
local.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
local.sin_port = htons(0x3412);

bind(s,(sockaddr*)&local,sizeof(local));

server.sin_family = AF_INET;
server.sin_addr.S_un.S_addr = htonl(INADDR_LOOPBACK);
server.sin_port = htons(0x1234);

connect(s,(sockaddr*)&server,sizeof(server));

send(s,buf,strlen(buf),0);
recv(s,recvbuf,sizeof(recvbuf),0);
closesocket(s);
WSACleanup();
return 0;
}

3.面向无连接的服务器：

#include <winsock.h>
#pragma comment(lib,"wsock32.lib")
int main(int argc, char* argv[])
{
SOCKET s;
sockaddr_in local;
sockaddr_in remote;
int len;
char buf[128];
WSAData wsa;

WSAStartup(0x101,&wsa);
s = socket(AF_INET,SOCK_DGRAM,0);

local.sin_family = AF_INET;
local.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
local.sin_addr.S_un.S_un_b = 9;
local.sin_port = htons(0x1234);

bind(s,(sockaddr*)&local,sizeof(local));
while(1){
len = sizeof(remote);
recvfrom(s,buf,sizeof(buf),0,(sockaddr*)&remote,&len);
len = sizeof(remote);
sendto(s,"ACK",3,0,(sockaddr*)&remote,len);

}
closesocket(s);
WSACleanup();
return 0;
}

4.面向无连接的客户机：

#include <winsock.h>
#pragma comment(lib,"wsock32.lib")
int main(int argc, char* argv[])
{
int len;
char *sndbuf = "I am a cl client";
char recvbuf[128];
WSAData wsa;

WSAStartup(0x101,&wsa);
s = socket(     );

local.sin_family = AF_INET;
local.sin_addr.S_un.S_addr = htonl(    );
local.sin_port = htons(    );

bind(  ,     ,sizeof(local));

remote.sin_family = AF_INET;
remote.sin_addr.S_un.S_addr = htonl(    );
remote.sin_port = htons(    );

len = sizeof(remote);
sendto(  ,sndbuf,16,0,    ,len);

len = sizeof(remote);
recvfrom(   ,recvbuf,sizeof(recvbuf),0,     ,&len);

closesocket(   );
WSACleanup();
return 0;
}