设置网络连接connect的超时时限

刺骨的言语ヽ痛彻心扉 2023-02-26 08:24 16阅读 0赞

### 设置网络连接connect的超时时限 ###

网上搜索的思路是一样的，该示例相对完整，已测试可用 。

#include <iostream>
    #include <WinSock2.h>
    #include <WS2tcpip.h>
    #pragma comment(lib,"ws2_32.lib")
    
    using namespace std;
    
    bool connect(char* host, int port, int timeout)
    { 
    	TIMEVAL Timeout;
    	Timeout.tv_sec = timeout;
    	Timeout.tv_usec = 0;
    	struct sockaddr_in address;
    
    	SOCKET sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    
    	//address.sin_addr.S_un.S_addr = inet_addr(host);
    	inet_pton(AF_INET, host, &address.sin_addr);
    	address.sin_port = htons(port);
    	address.sin_family = AF_INET;
    
    	//set the socket in non-blocking
    	unsigned long iMode = 1;
    	int iResult = ioctlsocket(sock, FIONBIO, &iMode);
    	if (iResult != NO_ERROR)
    	{ 
    		printf("ioctlsocket failed with error: %ld\n", iResult);
    	}
    
    	if (connect(sock, (struct sockaddr*)&address, sizeof(address)) == false)
    	{ 
    		return false;
    	}
    
    	//restart the socket mode
    	iMode = 0;
    	iResult = ioctlsocket(sock, FIONBIO, &iMode);
    	if (iResult != NO_ERROR)
    	{ 
    		printf("ioctlsocket failed with error: %ld\n", iResult);
    	}
    
    	fd_set Write, Err;
    	FD_ZERO(&Write);
    	FD_ZERO(&Err);
    	FD_SET(sock, &Write);
    	FD_SET(sock, &Err);
    
    	//check if the socket is ready
    	select(0, NULL, &Write, &Err, &Timeout);
    	if (FD_ISSET(sock, &Write)) 
    	{ 
    		return true;
    	}
    
    	return false;
    }
    
    int main()
    { 
    	WSADATA wsaData;
    	if (WSAStartup(0x0202, &wsaData) != 0)
    	{ 
    		printf("WSAStartup() error!\n");
    	}
    
    	char sIP[] = "10.168.33.10";
    	if (connect(sIP, 80, 2))
    		printf("OK\n");
    	else
    		printf("NO\n");
    
    	WSACleanup();
    	system("pause");
    	return 0;
    }

【参考文献】  
1、[https://blog.csdn.net/u011430225/article/details/77675259][https_blog.csdn.net_u011430225_article_details_77675259]

[https_blog.csdn.net_u011430225_article_details_77675259]: https://blog.csdn.net/u011430225/article/details/77675259