Atomic_write_ext.IOval rec_files : path -> string list Lwt.trec_files dir is the list of files recursively present in dir and all of its sub-directories. Return filenames prefixed by dir.
val file_exists : path -> bool Lwt.tfile_exist f is true if f exists.
val read_file : path -> string option Lwt.tRead the contents of a file using mmap.
val mkdir : path -> unit Lwt.tCreate a directory.