gethostbyname seems to return ipaddresses in reverse order for local host name on a multihomed machine.

Can you show that?

use Data::Dump;
dd [ gethostbyname 'localhost' ];
__END__
["VOL11", "", 2, 4, "\x7F\0\0\1"]
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I don't expect that gethostbyname is returning anything other than what gethostbyname is documented to return

#!/usr/bin/perl

use strict;
use warnings;
use Socket;

my $packed_ip = gethostbyname('localhost.localdomain');

if (defined $packed_ip) {
   my $ip_address = inet_ntoa($packed_ip);
   print $ip_address, "\n";
}
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Using Sys::Hostname::FQDN, you can do an ascii-version of Anonymous Monk's post like this:

#!/usr/bin/perl 

BEGIN {
    $|  = 1;
    $^W = 1;
}

use strict;
use warnings;
use Socket;
use Sys::Hostname::FQDN qw(
    asciihostinfo
    gethostinfo
    fqdn    
    short
);

my($name,$aliases,$addrtype,$length,@addrs) = asciihostinfo();

print qq|host info
  short name    : |, short(),   qq|
  long  name    ; |, fqdn(),    qq|
  aliases       : |, $aliases,  qq|
  address type  : |, $addrtype, qq|
  address length: |, $length,   qq|
  IP address(es):
|;

foreach(@addrs) {
    print "\t$_\n";
}
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I should have been clearer its the choice of ipaddress to return that's the issue. If I return all addresses it get it in a reverse order than a C# program (both are copied below). if I use Khen1950fx's first example I get the answer as 192.168.0.1 which is the wrong address to use. Code that picks the first address to use now breaks down on a multiadapter machines.

Outputs via C# and perl

>listaddrcsharp.exe 10.123.67.139 192.168.0.1

>perl d:\temp\in.pl 192.168.0.1 10.123.67.139

Perl code

use Socket;
use IO::Socket;

my $machineName = lc($ENV{COMPUTERNAME});
my ($name, $aliases, $addrtype, $length, @addrs) = gethostbyname($mach
+ineName);
foreach(@addrs)
{      
   ($a,$b,$c,$d)=unpack ('C4', $_);
   print "$a.$b.$c.$d\n";
}
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C# Code

 public static void Main(string[] args)
        {
            IPAddress[] ips;
            ips = Dns.GetHostAddresses(Environment.MachineName);

            foreach (IPAddress ip in ips)
            {
                if (ip.AddressFamily == AddressFamily.InterNetwork)
                    Console.WriteLine("    {0}", ip);
            }
        }
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Don't use pack, use inet_ntoa or whatever (same low level as gethostbyname, now lower like pack), common mistake

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