C++ determines whether the host is in network state
- 2020-06-07 04:51:36
- OfStack
The example of this paper shares the specific code of C++ to determine whether the host is in the state of networking for your reference, the specific content is as follows
Let the machine directly access to a website, if successful, it means that the successful networking, no access to the success, then no networking!!
#include<iostream>
#include <WINSOCK2.H>
#pragma comment(lib,"ws2_32.lib")
#define LEN 1024 // The size of the received data
using namespace std;
int main()
{
// Load the socket library
WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD( 1, 1 ); // Initialize the Socket Dynamic connection library , request 1.1 Version of the winsocket library
err = WSAStartup( wVersionRequested, &wsaData );
if ( err != 0 ) {
return 0;
}
if ( LOBYTE( wsaData.wVersion ) != 1 || // Judging the request winsocket Isn't it 1.1 The version of the
HIBYTE( wsaData.wVersion ) != 1 ) {
WSACleanup( ); // liquidation
return 0; // Termination of winsocket use
}
//WSADATA ws;
//WSAStartup(MAKEWORD(2,2),&ws);//
char http[60] = "www.google.com"; // Visit the Google page
SOCKET sock = socket(AF_INET,SOCK_STREAM,0);// To establish socket
if (sock == INVALID_SOCKET)
{
cout<<" Set up access socket The socket failed !"<<endl;
return 0;
}
sockaddr_in hostadd;
hostent* host = gethostbyname(http);// Acquired host IP address
if(host==NULL)
{
cout<<" The host is not connected ;"<<endl;
return 0;
}
cout<<" The host is networked and can now communicate !"<<endl;
memcpy(&hostadd,host->h_addr,sizeof(hostadd));// Returns the IP information Copy To address structure
hostadd.sin_family = AF_INET;
hostadd.sin_port = htons(80);
char buf[LEN]="GET / HTTP/1.1\r\nHost: ";// structure Http Request packet
strcat(buf,inet_ntoa(hostadd.sin_addr));
strcat(buf," \r\nContent-Length: 10\r\n\r\n");
strcat(buf,"Connection:close");
int time = 1000; // timeout
setsockopt(sock,SOL_SOCKET,SO_RCVTIMEO,(char*)&time,sizeof(time));
if (connect(sock,(sockaddr*)&hostadd,sizeof(hostadd)) == SOCKET_ERROR)// Connection request
{
cout<<" Failed to establish connection with web page !"<<endl;
return 0;
}
if (SOCKET_ERROR == send(sock,buf,strlen(buf)+1,0))// Transmit constructed Http Request packet
{
cout<<" Sending packet failed !"<<endl;
return 0;
}
memset(buf,0,LEN);
recv(sock,buf,LEN,0); // Receive the returned data
cout<<" The data obtained from the webpage is :"<<buf;
closesocket(sock);
WSACleanup();
return 0;
}