Thread: inet_aton()... Noob needs help with sockets :|

Hi dee Ho again.

I started learning how to toy with sockets yesterday... Well, I am utterly confused with the structures && functions dealing with ports & hostnames, with client & server sockets, with this & that

Basically what I would like to do is connect to certain server(s) & be able to send & receive data. I've done that with php sockets, so I assume I should be able to do it with c++ too

I prepared following class for that:
connect.h:

Code:

#ifndef _CONNECT
#define _CONNECT
#include <iostream>
#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

using namespace std;

class Connect {

private:

        int sock;
        struct sockaddr_in serv_addr;

public:
        Connect(){;}
        ~Connect()
                {
                close(this->sock);
                }
        int con(string host, int port); //open socket
        int send_command(string command);
        int send_payload(string command);
        char *receive();
};

#endif

and connect.cpp:

Code:

#include "connect.h"
#include <iostream>
#include <string.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <ctype.h>
#include <stdlib.h>
#include <netdb.h>

using namespace std;

int Connect::con(string host, int port)
{
        struct hostent *h;



        char *ip;

        //int success;


        if((h=gethostbyname(host.c_str()))==NULL)
        {
                herror("gethostbyname");
                exit(1);
        }

        ip=inet_ntoa(*((struct in_addr *)h->h_addr));


        if((this->sock = socket(AF_INET, SOCK_STREAM, 0)) < 0 )   //Lets make the filedescriptor
        {
                cout << "Smelly Socks!" << endl;
                exit(-666);
        }

        /*Lets connect to server*/
        serv_addr.sin_family = AF_INET;
        if( inet_aton(ip,&serv_addr.sin_addr) !=0 )
        {
                cout << "invalid ip format: " << ip << endl;
                exit(1);
        }
        serv_addr.sin_port = htons(port);

        if(connect(sock,(struct sockaddr *) &serv_addr, sizeof(serv_addr))<0)
        {
                cout << "Connecting to " << ip << " failed" << endl;
                exit(-666);
        }
        return 1;
}

int Connect::send_command(string command)
{
        int len;
        len=strlen(command.c_str())+2;

        command=command+"\r\n";
        write(sock,command.c_str(),len);
        cout << "SENT : " << command << endl;
        return 1;
}

int Connect::send_payload(string command)
{
        int len;
        len=strlen(command.c_str());
        cout << "SENT : " << command << endl;

        write(sock,command.c_str(),len);
        return 1;

}

char *Connect::receive()
{
        char *buf;
        int nread;
        nread=read(this->sock,buf,1024);
        cout << "GOT : " << buf << endl;
        return buf;
}

Now when I try to use it to connect to a certain server & send command inet_aton fails (it returns something that's not 0, and according to man pages it should not.)

(this

Code:

 if( inet_aton(ip,&serv_addr.sin_addr) !=0 )
        {
                cout << "invalid ip format: " << ip << endl;
                exit(1);
        }

Any ideas what's wrong? And can use this kind of class to do the connection? As I said, I am a noob with sockets, and the structures & handling of ip's / hostnames are mostly just taken from examples...

If someone feels like explaining them (structures & functions to manipulate hostnames/ips) well, feel free, (that would really help me understanding them better, cause the tutos I found just stated there is such structures, but the purpose is not terribly clear :/) but I would also be gratefull if someone just could tell me why inet_aton does not work.

Oh, BTW. I am using linux & g++ compiler.