opendir DH, $dir_to_process
# Use a lexical ($dir) instead of a bareword global (DH) if possible

##</code><code>##

if ($file =~ /\.txt$/) 
# This would break for a directory called dir.txt - see perldoc -f -X

##</code><code>##

%stuff_to_store = ($dir_to_process, $file);
# This overwrites the hash entirely every time

##</code><code>##

while (%stuff_to_store) {
# this will be an infinite loop if the hash contains any items