Forgive me if I've misunderstood what you're trying to do, but the following would yield an array of all the files (and directories) in a given directory:

my $path = 'yourdir/yoursubdir/';    # or whatever
my @filearray;
while (<$path*>) {
    s/$path//;            # strip off the filepath
    push @filearray, $_;  # push the filename into the array
}
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You can then use the array to generate the form fields on your page. If you wanted to get only files with, for example, extension .txt, you would use <$path*.txt>

(By the way, if you are new to perl - and I must say I only learnt this stuff a couple of months ago - you may wish to be reassured that the snippet above comes to much the same as

while (my $file = <$path*>) {
    $file =~ s/$path//;            
    push @filearray, $file;
}
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... though if you knew that already... well silly me.)

Sorry this is not a comprehensive solution: I hope it's some help.

§ George Sherston