uucp (unsigned)char

[utzoo!henry]

This message is a followon to the message I sent the other day about
(unsigned)c giving zero-extension when it shouldn't.  Note that the
uucp packet driver relies on this bug in a few places.  The fix is
to change "(unsigned)foo" to, ugh, "foo & 0377" in the appropriate
places.  I haven't done this yet and hence haven't identified exactly
which of the casts to unsigned in pk[01].c are affected.