#!/usr/bin/perl

use strict;
use warnings;

my    %FileInfo1 = ();

my ($inputFilename1, $inputFilename2, @otherParameters) = @ARGV;

# Read File 1 to Hash
open INPUT_FILE1, '<', $inputFilename1;
while (my $inputBuffer1 = <INPUT_FILE1>)
{
    chomp $inputBuffer1;
    my ($key, $data) = split /\|/, $inputBuffer1, 2;
    $FileInfo1{$key} = $data;
}
close INPUT_FILE1;

# Read File 2 and Compare
open INPUT_FILE2, '<', $inputFilename2;
while (my $inputBuffer2 = <INPUT_FILE2>)
{
    chomp $inputBuffer2;
    my ($key, $data) = split /\|/, $inputBuffer2, 2;
    if (!defined $FileInfo1{$key})
    {
        print "$key not found in $inputFilename1\n";
    }
    elsif ($FileInfo1{$key} ne $data)
    {
        print "$key data does not match\n";
        delete $FileInfo1{$key};
    }
    else
    {
        print "$key - OK\n";
        delete $FileInfo1{$key};
    }
}
close INPUT_FILE2;
foreach my $leftoverKey (keys %FileInfo1)
{
    print "$leftoverKey not found in $inputFilename2\n";
}

exit;

__END__

C:\Steve\Dev\PerlMonks\P-2013-10-08@1245-TwoFile-Keyed-Compare>type te
+st*.dat

test1.dat


A001|Steve|45
A002|George|32
A003|Alice|24

test2.dat


A001|Steve|45
A003|Alice|23
A004|Mike|48

C:\Steve\Dev\PerlMonks\P-2013-10-08@1245-TwoFile-Keyed-Compare>perl cm
+pfiles.pl test1.dat test2.dat
A001 - OK
A003 data does not match
A004 not found in test1.dat
A002 not found in test2.dat
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