Portability problems not fixed by Gnulib:
@itemize
@item
+This function is missing on some platforms:
+MSVC 9.
+@item
On platforms where @code{long int} is a 32-bit type, this function may not
work correctly on huge directories larger than 2 GB. The fix is to use
the @code{AC_SYS_LARGEFILE} macro (only on MacOS X systems).