CRITICAL FIX: kernel/sys/sys/rdwri.c

[utzoo!decvax!ucbvax!dist2]

	If UCB_BUFOUT is on but UCB_FSFIX is off, and an error occurs in
iomove(), writei() will not map out a buffer it had previously mapped in.
This will cause a ``panic:  mapin'' the next time mapin() is called.  The
following change should be made to all tapes written before 10/6/81:

	diff kernel/sys/sys/rdwri.c.old kernel/sys/sys/rdwri.c
	169d168
	< #ifdef	UCB_FSFIX
	171d169
	< #endif

			Carl