Im new at perl and this script is in its infacy. I am writing a script where the user is prompted to enter an IP address. From the address entered, the program will determine its subnet and compare it with a file containing a list of all the subnets on the network. The PROBLEM is that I cant get the script to check the list and compare the stored subnet address with the list. The troubled area is in red. Im pretty sure I am doing wrong in regards to accessing the list. Here is my code: 
#/usr/local/bin/perl 

# Creates a list of all subnets 
$sn = 0xffff & system("ypcat hosts | cut -f1-3 -d \".\" | sort -u | so
+rt -k 1n,1 
n -k 2n,2n -k 3n,3n -t \".\" -r>subnets.list"); 

# User is prompted to anter an IP address 
open(CHECK, ">check.list") || die "ERROR! This file cannot be created!
+\n"; 
print "Enter an IP address.\n"; 
$ip = <STDIN>; 
chomp ($ip); 
$partial = rindex($ip, "."); 
$ip_subnet = substr($ip, 0, $partial); 
chomp ($ip_subnet); 
print CHECK "$ip_subnet\n"; # Checkpoint - prints subnet 

# Match entered subnet to active subnet list 
open(SUBNET, "subnets.list") || die "Unable to open file: subnets.list
+\n"; 
while (<SUBNET> ) { 
if ($ip_subnet eq $subnet) { 
print "PASS\n"; 
} else { 
print "FAIL\n"; 
} 
}

[download]
So, for example, if the user enters 12.34.56.78, the program will store 12.34.56 as the subnet and then should compare 12.34.56 with the list subnets.list and return either a true or false value. Please HELP! Thanks. Zuinc

In reply to User input compared with generated list by zuinc

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