I've looked high and low for some answers to my dilemma. I need to search through a CSV file and find duplicate records, then write those records to another file. A typical file is 30,000+ records, about 4.3 Mb of text. I figured out how to use the following to remove the records, but I have to capture them so the charges can be reversed. 
open(CDR, $CDR);
     open(SORTED_CDR, ">$SORTED_CDR");
     @ARRAY=<CDR>;
     my @unique = do {my %h; grep {!$h {$_} ++} @ARRAY};
     print SORTED_CDR @unique;

[download]

In reply to print out duplicate records 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.