The command should delete files in the specified directory and all of its
sub-directories, using any file pattern specified.
For example, the command:
del /S .\my_directory
should delete all the files inside my_directory and its sub-directories,
and as such should also detect that "my_directory" is indeed a directory,
while doing:
del /S .\my_file
should of course detect that "my_file" is indeed a file pattern, and thus,
delete all "my_file" files from the current directory and its sub-directories.
The command:
del /S some_directory\file_pattern
should delete "file_pattern" files from some_directory and its sub-directories.