About gethostbyname() in winsock.

I think there should have entries of atleast local m/cs on your LAN in your etc/hosts file. If your OS is NT then you can find this folder in winnt\system32\drivers\etc\hosts. Or else find for etc. Here you should have entry for your default gateway.

Ajit

By entries I meant was atleast name of computer & its I.P.Address.

First try this piece of code:

    WSADATA data;
    char name[256];
    struct hostent *pHost;
    int rc;

    rc = WSAStartup(MAKEWORD(1, 1), &data);
    rc = gethostname(name, sizeof name);
    pHost = gethostbyname(name);

(run single-step and check result codes).

Does it work?

Do you have a valid DNS configured?
   

Perhaps my statement is not clear. My OS is Win95.
Anyway, many thanks.

I had tested alexo's code. and the result:
pHost is still NULL,
rc = -1,
(name = "https://www.experts-exchange.com" , "www.aol.com" or any
other host which I could reach)
my DNS is doubtless valid. otherwise I can hardly logon
this site.

thanks again.

Whoa, my code was supposed to check if the name/address of the *local* machine is resolved correctly.

Two versions:

////////////////////////////////////////////////////////////////////////////////

#include <winsock.h>
#pragma comment(lib, "wsock32.lib")

int main()
{
    WSADATA data;
    char name[256];
    struct hostent *pHost;
    int rc;

    rc = WSAStartup(MAKEWORD(1, 1), &data);
    rc = gethostname(name, sizeof name);
    pHost = gethostbyname(name);

    return 0;
}

////////////////////////////////////////////////////////////////////////////////

#include <winsock2.h>
#pragma comment(lib, "ws2_32.lib")

int main()
{
    WSADATA data;
    char name[256];
    struct hostent *pHost;
    int rc;

    rc = WSAStartup(MAKEWORD(2, 2), &data);
    rc = gethostname(name, sizeof name);
    pHost = gethostbyname(name);

    return 0;
}

////////////////////////////////////////////////////////////////////////////////

Hi,alexo:
sorry for my misunderstanding. Test your code again and it
works well except for that h_aliases is NULL, but I think
it make no difference. And If I change "name" to a remote
host it still return err. what's the problem? Can your help
me?
many thanks

>> Can your help me?
I can try...

Are you on a LAN?  Do you dial up?  Can you connect to other sites with a web browser or another client?

To alexo:

>>Are you on a LAN?
Yes.
>>Do you dial up?
No, but DDN E1 line.
>>Can you connect to other sites  with a web browser or another client?
Yes, I can. with either browser or any other client.

hi, alexo:

all right. it works. Thank you very much.
I find I have made a mistake compared with your code which
I ignored yesterday. your codes like this,

#include <winsock.h>
#pragma comment(lib, "wsock32.lib") "

and mine are:

"#include <winsock.h>
#pragma comment(lib, "ws2_32.lib")

That's the catch, but what's the difference?

BTW: How can I submit a FORM to accept your suggestion ?
now I can only add a comment here.