This example uses HTML::TokeParser to locate all of the META tags in a document.

#!/usr/bin/perl -w

use strict;
use HTML::TokeParser;

# get the file name to parse from the command line
my $html = shift or die 'Specify a file name';

# access the file with the parser
my $p = HTML::TokeParser->new($html) or die $!;

# loop through all tokens
while (my $r = $p->get_token) {
    # $r->[0] tells us if it's a Start tag, End tag, Text, Comment
    # for start tags, $r->[1] tells us the type of tag
    # only process META start tags
    next unless $r->[0] eq 'S' && $r->[1] eq 'meta';
    print "Found <meta> tag\n";
    # $r->[2] is a hash ref containing attributes and values
    while (my ($k,$v) = each %{$r->[2]}) {
    print "\t$k = $v\n";
    }
}
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Here's the result from running it against an html file on my system.

$ perl meta.pl ~/public_html/cvsbook.html
Found <meta> tag
        content = text/html
        http-equiv = Content-Type
Found <meta> tag
        content = Open Source Development With CVS
        name = description
Found <meta> tag
        content = makeinfo 4.0
        name = generator
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---
print map { my ($m)=1<<hex($_)&11?' ':'';
$m.=substr('AHJPacehklnorstu',hex($_),1) }
split //,'2fde0abe76c36c914586c';
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