How to get ip to hostname ?

Hello everybody . I have a text file , I want to compare ip with in line text
This is file text

Code:

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codeguru.com

c++.com
C#.com

google.com



c+++.com

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And this is my code

Code:

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#include <iostream>
#include <fstream>
#include <string>
#include <conio.h>
using namespace std;


string getip(string hostname)
{
        //function get ip
}

void main ()
{
    string string_main="http://abc-xyz.com/www/~av.123.456.789.000?url.aspx/etc";
       
        int count=0;

        string string_sub;
        ifstream infile;
        infile.open ("E:\\test.txt");

        while(!infile.eof()) // To get you all the lines.
        {
                getline(infile,string_sub); // Saves the line in string_sub.
              //  cout<<string_sub<<"\n"; // Prints our string_sub.

                        if (!string_sub.empty())
                        {
                                string temp=getip(string_sub); // get ip of string_sub on the text line by line
                                size_t result = string_main.find( temp ); //check string_sub on the text file line by line, comparable to string_main

                                if( result != string::npos )  // if found
                                {
                                        count+=1;
                                }
                        }
        }
        infile.close();
        //cout<< count <<"\n";
        if (count != 0)
        {
                cout << "Found\n";
        }
        else
        {
                cout << "Not found\n";
        }
getch();
}

---

Can you see it , How to create function get ip above ?
Thank you .

Here is an example http://msdn.microsoft.com/en-us/libr...(v=vs.85).aspx
See also this thread http://forums.codeguru.com/showthrea...ethostbyname()

Quote:

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Originally Posted by S_M_A

Here is an example http://msdn.microsoft.com/en-us/libr...(v=vs.85).aspx
See also this thread http://forums.codeguru.com/showthrea...ethostbyname()

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Hi S_M_A . I have read two topic at reference
In this case . can you build function in my code above ? . If possible , thank so much

Code:

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string getip(string hostname)
{
        //function get ip
}

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In addition , i try code of "OneEyeMan"

Code:

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#include "stdafx.h"
#include <WinSock2.h>

int _tmain(int argc, _TCHAR* argv[])
{
        WSADATA data;
        struct hostent *host;
        int result;
        DWORD error;
        result = WSAStartup( MAKEWORD( 2, 2 ), &data );
        if( result )
        {
                printf( "Error initializing sockets!\n\r" );
                return 1;
        }
        host = gethostbyname( "www.google.com" );
        if( !host )
        {
                error = WSAGetLastError();
        }
        return 0;
}

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And this is error
Attachment 30037
Thank

You obviously don't have a stdafx.h. How did you create the project and what MSVC version do you use?

Quote:

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Originally Posted by S_M_A

You obviously don't have a stdafx.h. How did you create the project and what MSVC version do you use?

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MVSC 2010 Pro v10.0.30319
I created project : New Project -> C++ ->WIn 32 console Aplication -> Empty Project . Then I add file .CPP to project.

1. Don't use conio.h/stdio.h. use iostream, which is more C++ oriented.

2. You have created an empty project, therefore there is no "stdafx.h" file, while copy/pasting the code, you've picked this one too, hence your compiler is complaining that it cannot find this file.

3. You also need to link with "ws2_32.lib", otherwise you'll started getting linking errors once you are done with compiler errors.

Following is the code for your reference.

Code:

---

#define WIN32_LEAN_AND_MEAN

#include <iostream>
#include <Windows.h>
#include <tchar.h>
#include <WinSock2.h>

#pragma comment(lib, "ws2_32.lib")        // Need to link with ws2_32.lib

int _tmain(int argc, _TCHAR* argv[])
{
        WSADATA data;
        struct hostent *host;
        int result;
        DWORD error;

        result = WSAStartup( MAKEWORD( 2, 2 ), &data );

        if( result )
        {
                std::cout << "Error initializing sockets!" << std::endl;
                return 1;
        }

        host = gethostbyname( "www.google.com" );

        if( !host )
        {
                error = WSAGetLastError();
        }
        return 0;
}

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Quote:

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Originally Posted by Ejaz

1. Don't use conio.h/stdio.h. use iostream, which is more C++ oriented.

2. You have created an empty project, therefore there is no "stdafx.h" file, while copy/pasting the code, you've picked this one too, hence your compiler is complaining that it cannot find this file.

3. You also need to link with "ws2_32.lib", otherwise you'll started getting linking errors once you are done with compiler errors.

Following is the code for your reference.

Code:

---

#define WIN32_LEAN_AND_MEAN

#include <iostream>
#include <Windows.h>
#include <tchar.h>
#include <WinSock2.h>

#pragma comment(lib, "ws2_32.lib")        // Need to link with ws2_32.lib

int _tmain(int argc, _TCHAR* argv[])
{
        WSADATA data;
        struct hostent *host;
        int result;
        DWORD error;

        result = WSAStartup( MAKEWORD( 2, 2 ), &data );

        if( result )
        {
                std::cout << "Error initializing sockets!" << std::endl;
                return 1;
        }

        host = gethostbyname( "www.google.com" );

        if( !host )
        {
                error = WSAGetLastError();
        }
        return 0;
}

---

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Hi Ejaz . i try it and i get many error . All of error in file "ws2def.h" 127 Error and 16 Warning
Attachment 30045

Hi Ejaz . I think I have libaray ws2_32.lib link. I have links and build, no errors, but can not get the result of running the IP of google.com
Attachment 30051

Your question was to resolve the errors, which are done. Please start separate thread for different problems (i.e. do no start multiple question in a single thread). Anyway, for this specific case, you need to do little more. Following code is for your reference.

Code:

---

#include <iostream>
#include <string>
#include <winsock2.h>

#pragma comment(lib, "ws2_32.lib")        // Need to link with ws2_32.lib

std::string get_ip( const std::string& hostname )
{
        hostent * host_info;
        WSADATA wsa_data;
        SOCKADDR_IN sock_addr;

        if ( WSAStartup( MAKEWORD( 1 , 1 ) , &wsa_data ) != 0 )
        {
                throw std::exception("WSAStartup Failed.");
        }

        host_info = gethostbyname( hostname.c_str() );

        if ( host_info == NULL )
        {
                throw std::exception("Unable to resolve host.");
        }

        memcpy( &( sock_addr.sin_addr ) ,
                        host_info->h_addr                ,
                        host_info->h_length );

        std::string ip = inet_ntoa( sock_addr.sin_addr );

        WSACleanup();

        return ip;
}

int main()
{
        try
        {
                std::string url("www.google.com");
                std::cout << "IP of " << url << " : " << get_ip( url ) << std::endl;
        }
        catch ( std::exception& e )
        {
                std::cout << e.what() << std::endl;
        }
}

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Hi Ejaz . can you see my code . I think www.google.com have six IP address as pic above :D :D

Code:

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#include <stdlib.h>
#include <iostream>
#include <fstream>
#include <string>
#include <conio.h>
#include <stdio.h>
#include <WinSock2.h> 

#pragma comment(lib, "ws2_32")

WSADATA wsaData; //golbal
//HOSTENT* list_ip;  golbal
IN_ADDR addr;  //golbal

using namespace std;

string getip(string hostname)
{
        HOSTENT* list_ip; // not golbal, in this function
                /*
                // convert string to char
                char c[1000];
                int so=hostname.size();
                for(int a=0;a<=so;a++)
                {
                        c[a]=hostname[a];
                }
                */
                if ( WSAStartup( MAKEWORD( 1 , 1 ) , &wsaData ) != 0 )
                {
                                cout << "WSAStartup Failed.";
                }
                else
                {
                        WSAStartup(MAKEWORD(2,0),&wsaData);
                        //list_ip=gethostbyname(c);

                        list_ip=gethostbyname(hostname.c_str()); //convert hostname from string to char

                        if (list_ip ==NULL)
                        {
                                //ExitProcess(0);
                                cout<<"Unable to resolve host.";
                        }
                        else
                        {
                                memcpy(&addr.S_un.S_addr , list_ip->h_addr, list_ip->h_length);
                                return inet_ntoa(addr);
                                WSACleanup();
                        }
                }
}

void main ()
{
    //string string_main="http://abc-xyz.com/www/~av.64.71.33.95?url.aspx/etc";

        //int count=0;

        string string_sub;

        ifstream infile("E:\\test.txt");

        if (!infile)
        {
                cout << "Unable to open file\n";
        exit(1); // terminate with error
        }
    while(!infile.eof()) // To get you all the lines.
        {
            getline(infile,string_sub); // Saves the line in string_sub.
            cout<<string_sub<<"\n"; // Prints our string_sub.
                       
                if (!string_sub.empty()) //check line have content
                {
                        string temp=getip(string_sub); //temp get ip from string_sub
                        cout << temp <<"\n"; //prints IP of hostname

                        //size_t result = string_main.find( string_sub ); //check string_sub on the text file line by line, comparable to string_main
                       
                        //if( result != string::npos )  // if found
                        //{
                        //        count+=1;
                        //        //cout << "String is found at position"<< infile.tellg() << "\n";
                        //}       
                }
    }
        infile.close();
        //cout<< count <<"\n";
        /*
        if (count != 0)
        {
                cout << "Found\n";
        }
        else
        {
                cout << "Not found\n";
        }*/
        //return 0;
getch();
}

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And this is test.txt file

Code:

---

msdn.com

c++.com
C#.com

google.com



c+++.com

---

But I can get IP address form hostname ?
Thank you so much if you try it .

Sample attached.

Code:

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E:\Temp\660>660.exe www.google.com
HostName: www.l.google.com
Alias[0]: www.google.com
 Host[0]: 173.194.32.50
 Host[1]: 173.194.32.49
 Host[2]: 173.194.32.52
 Host[3]: 173.194.32.51
 Host[4]: 173.194.32.48

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Hi . thank for your help
if you do not mind can see through my code, you can modify it slightly so that IP can print out. I think my jaw getip missing anything. Urge you to check out . I think in GetIP function

Code:

---

string getip(string hostname)
{
        WSADATA wsaData;
        IN_ADDR addr;
        HOSTENT* list_ip;
        //int i=0;
                if ( WSAStartup( MAKEWORD( 2 , 2 ) , &wsaData ) != 0 )
                {
                                cout << "WSAStartup Failed.";
                }
                else
                {
                        list_ip=gethostbyname(hostname.c_str()); //convert hostname from string to char
                        if (list_ip ==NULL)
                        {
                                //ExitProcess(0);
                                cout<<"Unable to resolve host.";
                        }
                        else
                        {
//                                while (list_ip->h_addr_list[i] != 0)
//                                {
//                                        addr.S_un.S_addr=*(u_long *)list_ip->h_addr_list[i++];
//                                        return inet_ntoa(addr);
//                                }
                                memcpy(&addr.S_un.S_addr , list_ip->h_addr, list_ip->h_length);
                                return inet_ntoa(addr);
                                WSACleanup();
                        }
                }
                WSACleanup();
}

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Hi all
I have already edit function getip . I think it`s ok , but get one IP from hostname

Take a look at the sample attached here by Igor, step through it with the debugger and see how it works.