I am new to Perl and in the process of learning.

I wrote a simple script to check two networks to see if the other hosts on those networks are up. I am sure that there is a better and more elegant way to do this. I'm open to any suggestions and/or pointers.

Here is what I have so far that is working. It's running on a Linux system if that matters.

#!/usr/bin/perl -w

use strict;

my $hostfile = "/etc/hosts";
my $pattern0 = "192.168";
my $pattern1 = "172.16";
my $eth_card0 = "eth0";
my $eth_card1 = "eth1";
chomp(my $ipaddr0 = `ifconfig | awk '/$eth_card0/ {getline; print}' | 
+awk '{print \$2}' | cut -d: -f2`);
chomp(my $ipaddr1 = `ifconfig | awk '/$eth_card1/ {getline; print}' | 
+awk '{print \$2}' | cut -d: -f2`);


open INPUT, '<', "$hostfile" or die "Cannot open $hostfile $!";
while (<INPUT>) {
    chomp;
    if ((/$pattern0/) or (/$pattern1/)) {
        my @hosts = split(" ", $_);
        foreach my $hosts (@hosts) {
            if (( $hosts =~ $pattern0 ) && ( $hosts ne $ipaddr0 ) ||
            ( $hosts =~ $pattern1 ) && ( $hosts ne $ipaddr1 )) { 
                pingip($hosts);
            }
        }
    }
}
close INPUT;

sub pingip {
    my $rhost = $_[0];
    my $retval = "";
    system("ping -c 1 $rhost > /dev/null");
    if ( $? != 0 ) {
        print "$rhost is not up\n";
    }
    else {
        print "$rhost is up\n";
    }
}

[download]

My specific questions are first and foremost, is there a better way to do this? Second, can some of you that know more about Perl than me point out some of the errors that I might have made?

This script isn't anything that is real important to me, I'm simply using it as a learning tool mainly on working with arrays, and eventually hashes.

Thank you in advance for your help

In reply to How do I check the status of a remote network by at2marty

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