Question

vc++ 多线程编程 SOCKET通信

#include <iostream>
#include <winsock2.h>
#pragma comment(lib,"ws2_32.lib")
using namespace std;
#include <process.h>

DWORD WINAPI ThreadFunc(LPVOID n)
{
SOCKET ssock;
ssock=(SOCKET)(LPVOID)n;
char buf[1000];
while(1){
recv(ssock,buf,1000,0);
if(buf==("exit"+'\0'))
break;
else
cout<<buf<<endl;
}

return 0;
}
int main(){
SOCKET sock;

sockaddr_in serveraddr;
WSADATA wsaData;
WSAStartup(0x202,&wsaData);
sock = socket(AF_INET, SOCK_STREAM, 0 );
memset((void *)&serveraddr, 0, sizeof(serveraddr));

serveraddr.sin_family = AF_INET;
serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);
serveraddr.sin_port = htons(8888);

bind(sock,(sockaddr *)&serveraddr, sizeof(serveraddr));
listen(sock,SOMAXCONN);

while(1)
{
SOCKET ssock;
ssock=SOCKET_ERROR;
while(ssock==SOCKET_ERROR)
{
ssock=accept(sock,NULL,NULL);
}
printf("Client Connected.\n");
DWORD dwThreadId;
HANDLE hThread;

hThread=CreateThread(NULL,NULL,ThreadFunc,
(LPVOID)ssock,0,&dwThreadId);
CloseHandle(hThread);
Sleep(400000);
closesocket(ssock);
}

WSACleanup();
system("pause");
return 0;
}

服务端主程序如上,为何只能同时接受一个用户的连接,而不能同时接受多个用户的连接

Answer 1

你给客户端发送数据是用send么
如果没Sleep的话，你创建了一个新线程，创建新线程的同时，当前线程也在运行，socket都被你关掉了，还怎么send？？
线程跟函数是不同的，函数是等调用结束后才执行下一个语句