cjones@monster:~/snmpscripts$ cat testcase02.pl
#!/usr/bin/perl

use Net::SNMP;
use strict;
use warnings;

my $community           = "eX0gyN37";
my $inputfilename 	= "/home/cjones/snmpscripts/hostipaddresses.txt";
my $HOSTNAME_OID        = "1.3.6.1.4.1.9.2.1.3.0";

open my $input, '<', $inputfilename or die "$0: $inputfilename: $!\n";

while (my $ip = <$input>) {

	$ip =~ s/\n//;
        $ip =~ s/\r//;

	print "IP: $ip\n";
	
	my ($snmp,$snmperror)   = Net::SNMP->session(
                -hostname       => $ip,
                -community      => $community
        	) or die "SNMP Session ERROR: $!";

	my $response 		= $snmp->get_request(
		$HOSTNAME_OID
		) or die "SNMP get ERROR: $!";

	my $hostname		= $response->{"$HOSTNAME_OID"};

	die "Hostname isnt being defined for some reason\n" unless defined $hostname;


}
cjones@monster:~/snmpscripts$ perl testcase02.pl 
IP: 192.168.0.254
SNMP get ERROR:  at testcase02.pl line 25, <$input> line 1.
cjones@monster:~/snmpscripts$ cat hostipaddresses.txt 
192.168.0.254
192.168.0.1
192.168.0.4
192.168.0.5
192.168.0.9
cjones@monster:~/snmpscripts$