* replace pointer acrobatics with a struct
* make sorting explicit: MY_DONT_SORT -> MY_WANT_SORT
(if you want something to be done - say it. fixes all places where
my_dir() was used without thinking)
* typo s/number_off_files/number_of_files/
* directory_file_name() doesn't need to be extern
* remove #ifdef __BORLANDC__
* ignore '.' and '..' entries