This function is missing on some platforms:
MSVC 9.
@item
-On MacOS X platforms where @code{long int} is a 32-bit type, this function may
+On Mac OS X platforms where @code{long int} is a 32-bit type, this function may
not work correctly on huge directories larger than 2 GB.
(Cf. @code{AC_SYS_LARGEFILE}.)
@end itemize