I'm new to using perl. Basically what I'm trying to do is slice up a csv file and perform two actions with it, one iterate through certain columns and confirm DNS entries exist for certain systems and they are accurate and output anything that doesn't match and secondly generate nagios configuration files for any entry which has an IP address. I'm stuck at this point, my code states "Use of uninitialized value $hostip in string at C:/Users/akuncewitch/workspace/Sec Ops Engineering Toolkit/nagiosgen.pl line 15, <F> line 1." When I run it but I have no idea what I'm missing. I've written several fairly simple Perl scripts that sliced up csv and even performed actions in a loop, so I'm not sure what I'm missing this time.

perl 5, version 12, subversion 4 (v5.12.4) built for MSWin32-x64-multi-thread Binary build 1205 294981 provided by ActiveState http://www.ActiveState.com Built Jun 20 2011 18:11:54 

use warnings;


#Read Security Engineering Inventory CSV Export and puke @ failure
my $file = 'C:/perl64/seceng.csv';
my $hostpath = 'C:/perl64/nagios/hosts/';
#my $hostpath = '/usr/local/nagios/etc/objects/hosts/';
open (F, $file) || die ("Could not open $file!");

while (<F>)
{
    @fields = split(',', $_);
    $hostname = $fields[3];
    $hostip = $fields[5];
    if(-e "$hostip"){   
    open (HOST, 'C:/perl64/nagios/hosts/' . $hostname) || die "Couldn'
+t open: $!";
    printf HOST "define host\{";
    printf HOST "use    linux-server;\n";
    printf HOST "host_name    $host;\n";
    printf HOST "alias        $host;\n";
    printf HOST "address $hostip;\n";
    printf HOST "\}";
    }
} 

close F;

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In reply to Question on loops and variables by bogonspace

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