2002-08-27  Conrad Scott  <conrad.scott@dsl.pipex.com>

	* fhandler.h (fhandler_base::readv): New method.
	(fhandler_base::writev): Ditto.
	* fhandler.cc (fhandler_base::readv): New method.
	(fhandler_base::writev): Ditto.
	* syscalls.cc (_read): Delegate to readv(2).
	 (_write): Ditto, mutatis mutandi.
	(readv): Rewrite, based on the old _read code, to use the new
	fhandler_base::readv method.  Improve access mode handling and
	ensure all calls reach the final strace statement.
	(writev): Ditto, mutatis mutandi.
	* include/sys/uio.h (struct iovec): Change field types to match SUSv3.
	* winsup.h (check_iovec_for_read): New function.
	(check_iovec_for_write): Ditto.
	* miscfuncs.cc (check_iovec_for_read): Ditto.
	(check_iovec_for_write): Ditto.