Mavericks suggestion to set the input record separator to 0x0c will allow you to read in one record at a time and avoid all that mucking around with single characters. It will no doubt speed your code considerably as well as simplifying it quite a lot. Let Perl work for you.

Here is a small optimisation of your last two subs that will save a bit of time too. By using the 'x' operator rather than a while loop we add our whitespace pad in one operation. By using a regex to stip leading and trailing whitespace we save a lot of mucking about and let the regex engine do the work. This too will be much faster. 

# Pad out with trailing whitespace as necessary
sub pad {
    my ($data, $len) = @_;
    my $pad = $len - (length $data);
    $data .= " " x $pad unless $pad < 0;
  return $data;
}

# Get rid of leading/trailing whitespace
sub normalise {
    my $value = shift;
    $value = s/^\s+|\s+$//gm;
  return $value;
}

[download]

Hope this helps

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: Perl scripts slowing down towards end of file processing by tachyon
in thread Perl scripts slowing down towards end of file processing by JPaul

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.