If I'm understanding you correctly, you're interested in finding all items in the first file that are not in the second file. If this is the case, List::Compare can assist you with this:

use strict;
use warnings;
use File::Slurp qw/read_file/;
use List::Compare;

chomp( my @a_file = read_file 'a_file.txt' );
chomp( my @b_file = read_file 'b_file.txt' );

my @a_file_only = List::Compare->new( \@a_file, \@b_file )->get_Lonly;

print "$_\n" for @a_file_only;

[download]

Output on your data sets:

http://www.ok.com/test_1234.html
http://www.ok.com/test_error.html

[download]

Hope this helps!

In reply to Re: Compare two txt files and print the difference between the two files. by Kenosis
in thread Compare two txt files and print the difference between the two files. by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.