@item
This function is missing on some platforms:
MacOS X 10.3, FreeBSD 5.2.1, NetBSD 3.0, mingw, BeOS.
+@item
+On platforms where @code{off_t} is a 32-bit type, this function may not
+correctly report the size of files or block devices larger than 2 GB.
+The fix is to use the @code{AC_SYS_LARGEFILE} macro.
@end itemize