Notes on xcalc:

I've gotten the sucker to run on an IBM RT, under BSD 4.2, and on a MicroVAX 
GPX, under Ultrix 1.2.  The RT is lucky enough to have the IEEE math routines.
Under these routines, if you say "x = 1.0 / 0.0", it doesn't blow up.  
Instead, when you decide to printf() x, it shows up as "INF".  The routines
also have the nice feature of being terribly accurate.  Needless to say, this
all makes writing a calculator fun/E-Z.

On the MicroVAX, however, I had to use a wretched math package, one that only
goes between 1E-38 and 1E+38, one that isn't very accurate, and one that will
cause an FP Exception at the slightest prompting.  As a result, I had to put
in all sorts of evil nasty 'sigvec's and 'setjmp's and things.  I think it
takes away from the intrinsic beauty (hah!) of the code, but at least it 
doesn't say "floating exception:  core dumped" anymore, so it's a step in
the right direction.

The point is:  If you're lucky enough to have the IEEE routines, by all means 
add a -DIEEE to the CFLAGS line in the Makefile.

-jhb, 3/16/86
