I'm going to try to remember this trick:

{
    my %opt;
    getopts("hf:d:") || die HELP();

    sub opt_h { exists $opt{h} ? 1 : 0 }
    sub opt_f { exists $opt{f} ? 1 : 0 }
    sub opt_d { exists $opt{d} ? 1 : 0 }
}
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But if a given option takes an argument, wouldn't this be the way to go:

{
    my %opt;
    getopts("hf:d:") || die HELP();

    sub opt_h { exists $opt{h} ? 1 : 0 }
    sub opt_f { exists $opt{f} ? $opt{f} : '' }
    sub opt_d { exists $opt{d} ? $opt{d} : '' }
}
if ( opt_f eq "foo" ) {
   ...
}
# usw, etc.
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There's just that little issue about remembering to leave off the $ sigil when testing the options -- some habits are hard to unlearn (but "use strict" will cover that).