Just a few tricks. Don't use chained if statements when a hash will do: 
my %month = (
        Jan => 0,
        Feb => 1,
        ...
);

# ...

$month = $month{$month};  # Could stand to use better names

[download]
In many cases it's often better to make a big regex for the entire line. A fully-expanded line-matching regex can break out all the variables you need without any leftover material that needs to be stripped off with substitutions.

Alternatively, you could use something like Apache::ParseLog.

Also, since you've left out the brackets on your open call, it doesn't actually error out when you expect it to. The correct way would be:
open(LOGFILE, "datafile.html") || die "Can't open file";
Further, you can actually iterate over the log file one line at a time instead of reading it all in: 
foreach my $log_line (<LOGFILE>)
{
     # ...
}

[download]
By the way, that commented out #use strict; is scary. The reason you're getting errors is because you're not properly declaring your variables with my. For example: 
my $hour = param ("hour");
my $minute = param ("minute");

[download]

In reply to Re: Pulling by regex II by tadman
in thread Pulling by regex II by mkent

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.