public inbox for gcc-help@gcc.gnu.org
 help / color / mirror / Atom feed
From: snodx@hotmail.com
To: gcc-help@gcc.gnu.org
Subject: Re: IP ADDRESS OF MACHINE
Date: Wed, 27 Feb 2002 09:17:00 -0000	[thread overview]
Message-ID: <248230825.1014814965869.JavaMail.root@naini.zyberway.com> (raw)

Greetings,
           Thanks to Stephano Mariani and Robert Lopez for their inputs.

            Robert Lopez wrote:
             >The GNU C Library Reference Manual might be useful to you. See the
sections on Host Addresses and  Host Names in the Sockets section.

            Where can I get the GNU C Library Reference Manual?

            Stephano Mariani wrote:

            >See `man gethostbyname`

            I gather that you suggested that I use this function which exists in the netdb.h header file

            I wrote the following C program:

            #include<unistd.h>
            #include<netdb.h>

            main()
            {
              int snodsize=12;
              char snodarr[100],arrsnod[100],*sndptr,*snodptr,**snodptrptr;
              struct hostent *hstptr;

              sndptr=snodarr;
              snodptr=arrsnod;
              snodptrptr=&snodptr;

                gethostname(sndptr,(size_t)snodsize);

              hstptr=gethostbyname(sndptr);
              snodptrptr=hstptr->h_addr_list;

                printf("%s",*snodptrptr);
            }
___________________________________________________________________________________________________

        The program is simple to understand:

        It declares a pointer to a character ARRAY called sndptr

        It declares another pointer to another character array snodptr

        It declares a pointer to a character pointer called snodptrptr

        It retrieves the hostname of the current system using gethostname of unistd.h

        It retrieves a pointer to a hostent structure using gethostbyname of netdb.h

        Next I equate the pointer-to-character-pointer variable snodptrptr
        to the h_addr_list field of the hostent structure. This is because
        h_addr_list is the most likely field where the IP Address might be
        stored and it is a pointer-to-pointer which cannot be accessed directly.
        Hence snodptrptr

        I display snodptrptr.

        But I am not getting the IP Address as I wanted it.
__________________________________________________________________________________________________

         What am I doing wrong? Are there any modifications in the code?
         SNODX

             reply	other threads:[~2002-02-27 13:13 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-02-27  9:17 snodx [this message]
2002-02-27 19:32 ` Andrea 'Fyre Wyzard' Bocci
2002-02-28  6:03   ` Nelson Guedes Paulo Junior
2002-02-28  6:49     ` John Love-Jensen
2002-02-28 10:15       ` Nelson Guedes Paulo Junior
2002-03-01  6:34         ` John Love-Jensen
2002-03-05  1:07     ` Bharathi S
     [not found] <616BE6A276E3714788D2AC35C40CD18D53345D@whale.softwire.co.uk>
2002-03-05  1:18 ` Rupert Wood
     [not found] <616BE6A276E3714788D2AC35C40CD18D47C245@whale.softwire.co.uk>
2002-02-28  5:39 ` Rupert Wood
  -- strict thread matches above, loose matches on Subject: below --
2002-02-28  4:04 snodx
2002-02-28  4:30 ` Michal Lipták
2002-02-28  3:56 snodx
2002-02-28  3:25 snodx
2002-02-28  3:55 ` Edmund Green
     [not found] <616BE6A276E3714788D2AC35C40CD18D47C203@whale.softwire.co.uk>
2002-02-28  2:43 ` Rupert Wood
2002-02-28  1:38 snodx
2002-02-27  5:13 snodx
2002-02-26 18:29 Robert Lopez
2002-02-26  4:18 snodx
2002-02-26  5:46 ` Stephano Mariani
2002-02-28 14:02 ` Florian Weimer
2002-02-26  0:35 snodx
2002-02-26  1:29 ` Frank Schafer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=248230825.1014814965869.JavaMail.root@naini.zyberway.com \
    --to=snodx@hotmail.com \
    --cc=gcc-help@gcc.gnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).