#!/usr/bin/perl -w
################################
 
use strict;
 
open(PIPE,'netstat -i|') or die $!;
 
my $header=<PIPE>; # Kernel Interface Table
$header=<PIPE>;    # The real header
chomp $header;
 
#
# Oh... what the hey... Let's parse it just for grins.
my @fields=split(/[\s]+/,$header);
 
my %ifTable=();   # Set up an empty assoc array
while (my $line=<PIPE>){
    chomp $line;
    my @f=split(/[\s]+/,$line);
    foreach my $ix(1..$#f){
        $ifTable{$f[0]}->{$fields[$ix]}=$f[$ix];
    }
}
 
#
# But wait... you just wanted the IF names:
 
printf "%s\n",join(",",keys %ifTable);
 
     

##</code><code>##

vmnet1,lo,wlan0,vmnet8,eth0

##</code><code>##

:
: much handwaving here
my @results=grep /eth1/,`netstat -i`;
: 
: I didn't test that, but should work...
:

##</code><code>##

:
: 
print "It's there\n" if $ifTable{'eth1'}; # or whatever
:
: