You could use readdir instead. It's a bit verbose relative to using glob, but it works.

#!/usr/bin/perl -wT

use strict;
delete @ENV{qw(IFS CDPATH ENV BASH_ENV)};
my $dir = '/var/www/htdocs';
opendir(DIR, $dir) or die "Can't opendir $dir: $!\n";
my @entries = map { /\.html\z/ ? "$dir/$_" : () } readdir(DIR);
closedir(DIR);
[download]

The map is doing two things here: grabbing only the files that end in .html, and prepending the path to mimic the behavior of the glob.