Re: Showing value of a s/g

[Harry Binswanger hb@xxxxxxxx]

Fred Weiner wrote:


Harry Binswanger wrote:
> I've forgotten how to display the contents of a s/g with a command-line
> entry. It's not va/nv @50 (for s/g 50). Pardon my lapse, but what is the
> way again?

Certainly that is the way to show s/g contents on the command line! For
example, if I type: 'va/nv @652' on the system I'm using, having run
GetXYOS in http://startup.intstartup.int, the prompt line shows
'XyOS=DOS'. Harry, you're not using the , are you? That delivers
the 'Application error' message . . .


Thanks. The problem was that none of the low order variables (numbers below
100) were initialized. I guess it's obvious that not having a program
running means those below 100 lose their contents, but I didn't realize
that they also go out of existence (lose their initialization). I found
this out by looking through a 2002 post from Carl on Xy4 programming. He
points out that if VA!01 returns 255 then 01 is not initialized. So I
tried, on the command line, VA/NV !01 and sure enough, it displayed 255. So
did all the double-digit ones, even those I'd just set in a program. In
order to get the VA/NV @01 response I (naively) expected, I had to run that
from within a program:

BC va/nv @10XC 
which worked.

Further searching of the U2 has revealed CASG, which puts the contents of
any (initialized) s/g into the text window. So the problem is solved. I
knew this feature had to be in the U2, and I found it by SEarching for @01.
I expedited the search by preceding the @01 with a not-R, to skip all the
's.


I was at first confused by the fact that CASG 50 shows a string,
when VA/NV !50 returns 255. But it must be that the routine CASG itself, or
one of its daughter routines, sets 50, so it isn't an exception to the
dictum that exiting a program or frame un-initializes the S/Gs 0-99.



Harry Binswanger
hb@xxxxxxxx