
  -spec make_dir(Dir) -> ok | {error, Reason}
                    when Dir :: name_all(), Reason :: posix() | badarg.

  Tries to create directory Dir. Missing parent directories are 
  not created. Returns ok if successful.

  Typical error reasons:

  eacces:
    Missing search or write permissions for the parent directories
    of Dir.

  eexist:
    A file or directory named Dir exists already.

  enoent:
    A component of Dir does not exist.

  enospc:
    No space is left on the device.

  enotdir:
    A component of Dir is not a directory. On some platforms, 
    enoent is returned instead.
