draconis,
robartes has pointed you in the right direction. Read the docs on stat.

You can import symbolic mode constants (S_IF*) and functions (S_IS*) from the Fcntl module:
S_IFREG S_IFDIR S_IFLNK S_IFBLK S_ISCHR S_IFIFO S_IFSOCK S_IFWHT S_ENFMT

Figure the bitwise math out and create a hash lookup.

Cheers - L~R