From owner-freebsd-questions  Mon Sep  2 18:18:28 2002
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Date: Tue, 3 Sep 2002 11:18:15 +1000
From: Edwin Groothuis <edwin@mavetju.org>
To: Tony <tony@idk.com>
Cc: freebsd-questions@freebsd.org
Subject: Re: Need help: gethostbyaddr
Message-ID: <20020903011815.GY785@k7.mavetju>
Mail-Followup-To: Edwin Groothuis <edwin@mavetju.org>,
	Tony <tony@idk.com>, freebsd-questions@freebsd.org
References: <200209030021.RAA19794@idk.com>
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On Mon, Sep 02, 2002 at 05:21:50PM -0700, Tony wrote:
> I just cannot seem to understand the function gethostbyaddr, more what and
> how would one lookup an ip number.
> 
> All I want to do it write a program to look up one ip number to it's host
> name. I am very confused with this function.
> 
> Example?

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>

int main(void) {
	struct hostent *h;
	struct in_addr in;

	inet_aton("212.204.230.141",&in);

	h=gethostbyaddr((char *)&in,4,AF_INET);

	printf("%s is %s\n",inet_ntoa(in),h->h_name);

	return 0;
}

Edwin

-- 
Edwin Groothuis      |            Personal website: http://www.MavEtJu.org
edwin@mavetju.org    |    Weblog: http://www.mavetju.org/weblog/weblog.php 
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