ocaml-unix-dirent provides
access to the features exposed in dirent.h in a way that is not
tied to the implementation on the host system.
The Dirent module provides functions for translating
between the file kinds accessible through dirent.h and their values
on particular systems.
The Dirent_unix provides bindings to functions that use the
types in Dirent along with a representation of the host system. The
bindings support a more comprehensive range of file kinds than the corresponding
functions in the standard OCaml Unix module. The
Dirent_unix_lwt module exports non-blocking versions of
the functions in Dirent_unix based on the Lwt cooperative threading
library.