What does your current code look like? You may like to mock up a test script using a __DATA__ section to simulate the "input data" for the script.

How you solve the problem depends a lot on whether you must parse the existing HTML document to determine what past lines were, or if you have them available in some other fashion and can simply recreate the HTML file with the new data.

HTML::TreeBuilder will help a lot if you have to parse the data and HTML::Template will help generate the new file. At some point an array slice (see perldata - slices) will help extract the last five lines.

DWIM is Perl's answer to Gödel

In reply to Re: truncating a text file by GrandFather
in thread truncating a text file by dankichi

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.