82 Shell BUG PIN-POINTED!!!


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82 Shell BUG PIN-POINTED!!!



Well, not exactly, but here is what happens when you do math in the TI-OS,
which in turn causes the calc to crash.  I have a possible solution, but
shell developers won't like it.

Remember Jimmy Mardell's 'Online ZShell School'?  Most of us remember that
the variables, programs, etc. are constantly moving about in memory.  This
moving of variables doesn't occur when a shell is running, so that is no
problem.  Its when you return to the TI-OS, that you have the problem.
What happens when you do a math problem?  Here is my educated guess as to
what occurs:

1) You type in a math problem and press enter.
2) Your math problem/ANS is stored on the VAT (Variable Allocation Table)
(moving some variables around to make space in some cases).
3) The calculator does the calculation.
4) Repeat the steps.

Number 2 is the major problem.  Why?  Matrix 5 has a mis-reported size.
This means that when the calculator goes to move the variable, it can't
find the end of it causing the calculator to lock-up.  Its a little more
complicated that this, but that is the basic concept.

SOLUTION:  The only solution that I can think of for this, is to find a way
to get a termination byte on it, yet to still have the "matrix" be a pointer.


                 Thomas J. Hruska -- thruska@tir.com
Shining Light Productions -- "Meeting the needs of fellow programmers"
         http://www.geocities.com/SiliconValley/Heights/8504
                    http://shinelight.home.ml.org