pac - core dumps and oddities (with fixes)

[Guy Harris]

>I've just been looking at pac, the calculator.  It seems a fairly nice piece
>of work (shame it doesn't work on Sun3s...anyone know a fix for this ?).

The introductory section of the posting correctly notes that the problem
has nothing whatsoever to do with Sun-3s; the problem is that it doesn't
work under SunOS 3.x.  The "Relnotes" file reflects the author's old
incorrect belief that the problem was with Sun-3s, not with 3.x (the
only Sun-3's on which he'd tried it were running 3.x; I got it to run on
a Sun-3 running 4.0.3 with no problem), and should be updated to reflect
the fact that the problem is with 3.x's "curses" library, not with the
Sun-3.

>There are however a few buglets/wierdos.
>
>It tries to write to constant strings in a few places---instant core dump with
>ANSI compilers.

Nope.  Instant core dump with those compilers - ANSI or non-ANSI - that
put constant strings into read-only portions of the address space.  ANSI
does *NOT* mandate that this happen, it only *permits* it.  GCC, for
instance, has, as I remember, a flag "-fwritable-strings" or somesuch
that tells it not to put constant strings into read-only portions of the
address space.