Comparing 2 files without diff or compare

ilottl has asked for the wisdom of the Perl Monks concerning the following question:

Please help, I am trying to compare 2 files to output: - What is in the second file that is not in the first - What is in the first file but not in the second. - What are the duplicates between the 2 files The below is all I have but it is proving damn difficult. Any help would be great!

#!/usr/bin/perl -w
#use strict;


$file1= "StatusRegs.txt";
$file2 = "RegsUNQ.txt";

open (ONE, $file1) or die "Couldn't open $file1: $!\n";
open (TWO, $file2) or die "Couldn't open $file2: $!\n";

while ($line1 = <ONE>) { 


    $line2 = <TWO>; 


    if ($line1 ne $line2) {  
        print "$line1 does not equal $line2 at line $.\n"; 
    } else {
        print "$line1 is the same in both files at line $.\n";
    }
}
[download]

Comment on Comparing 2 files without diff or compare Download Code

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Re: Comparing 2 files without diff or compare by Zaxo (Archbishop) on May 02, 2007 at 01:49 UTC
`use Algorithm::Diff;` [download] Algorithm::Diff is a perl implementation of system `diff`. The presence of unix utilities is unnecessary and no fork is needed. After Compline, Zaxo	[reply] [d/l]
Re: Comparing 2 files without diff or compare by merlyn (Sage) on May 02, 2007 at 06:59 UTC
Untested, but it usually works, and written in a way that if this is homework, someone will notice. `sub slurp { local ARGV; @ARGV = @_; <> } my %where; $where{$_} .= "1" for slurp($file1); $where{$_} .= "2" for slurp($file2); for (sort keys %where) { my $where = $where{$_}; if ($where =~ /12/) { print "both"; } elsif ($where =~ /1/) { print "left"; } else { print "right"; } print ":\t$_"; }` [download] -- Randal L. Schwartz, Perl hacker update:* Yeah, oops, thanks akho. Fixed.	[reply] [d/l]
Re^2: Comparing 2 files without diff or compare by akho (Hermit) on May 02, 2007 at 08:29 UTC
Doesn't always work, actually. What if `$where eq '11111222'`?	[reply] [d/l]
Re: Comparing 2 files without diff or compare by ilottl (Novice) on May 02, 2007 at 02:12 UTC
Unfortunately that module is not available on the XP system. Error: Can't locate Algorithm/Diff.pm in @INC contains...	[reply]
Re^2: Comparing 2 files without diff or compare by GrandFather (Saint) on May 02, 2007 at 02:22 UTC
Assuming that you are using Active State Perl use ppm to install it (see A guide to installing modules for Win32). If you are not using AS Perl, see A Guide to Installing Modules for a guide to installing modules from CPAN. DWIM is Perl's answer to Gödel	[reply]
Re^3: Comparing 2 files without diff or compare by ilottl (Novice) on May 02, 2007 at 06:48 UTC
Got it installed just got to figure out how to use it.	[reply]