de-Bourned; reformatted to Joy Normal Form

old SDB relics clobbered

linted

some work done to prepare for /proc and discarding of ptrace
interface.  Reading sequences of bytes using ptrace is now done
portably, and considerably more efficiently for commands that
repeatedly fetch objects smaller than an `int' (e.g., `l' command, `s'
and `S' formats).

adb used to accept 0t, 00t, 0<overflow-to-0>t, etc as decimal, and so
forth.  now only the advertised sequences (and their uppercase
counterparts) are accepted: 0x, 0X, 0t, 0T, 0o, 0O.

"unexpected ')'" error is gone; you now get "bad command".

fixed crash if you asked for <expr> # 0

fixed crash on input like 0.999999999999999999999999999999999999999

some expressions using variable 0 may behave differently.  In
particular, it used to be that `8000=C;<0=X' would first print ^@, then
print 8000.  Now the =C truncates, so that you get 0 instead of 8000.

finally got rid of that stupid
	_foo:
	_foo:	0
output format.  _foo appears exactly once now.  (This may need some
further work.)

reenabled the 1, 2, and 4 formats (not that 2 and 4 are needed, as they
are the same as w and W).  To get these you must write \1, \2, or \4,
or the code will assume (as it used to) that these are prefix counts.

the VAX instruction decoder will now print comments in some questionable
situations that sometimes arise when attempting to print data as
instructions.  Previously it would print nonsense and rely upon the
user to discover it as nonsense.

fixed radix code (previously everything that was not hex was decimal)

expression>pc now works as an alternate method for changing the pc
(the usual expr:r, expr:s, expr:c formats still work).

fixed annoying VAX feature that printed clrl/clrf instructions as
clrf instructions, and likewise for mova and pusha: now l is preferred
to f, q to d, etc., when two instructions have the same opcode.

8a format no longer prints dot 9 times.  I doubt anyone will miss this...

radix code now works more the old tahoe adb: a negative radix tells
adb to print negative numbers with leading `-'; else all are assumed
unsigned.  The new (internal and external) `v' and `V' formats print
in the current radix, but always signed (used by, e.g., the vax
instruction disassembler, for fp offsets).