Re: running .system files from BASIC

[mjmahon@aol.com (Michael J. Mahon)]

Don Bruder wrote:

>In article <40709349.26C1@alumni.utexas.net>,
> Robert Boucher <boucher1@alumni.utexas.net> wrote:
>
>> If you old enough, you know that D$ was almost universally used for
>> CHR$(4). Therefore, 
>> 
>> 10 D$=CHR$(4)
>> 20 ?D$"-program to run"
>> .
>> .
>> .
>> .
>> 150 ?D$"-another program to run"
>
>Except for one minor detail:
>It's *VERY* likely that like 150 won't exist after line 20 executes - A 
>.system program (which, coincidentally, is what "basic.system" is) 
>*MUST* load at $2000, and begin execution at that same location. Whether 
>it's "smart" enough to move itself out of the way after being loaded is 
>one of the big questions. I believe basic.system does, but I can't swear 
>to it anymore. Even if it does, there's no predicting what kind of 
>memory-stomping dance the next .system file is going to perform, so 
>there's no guarantee that basic.system (or the basic program that was 
>running under it) will be intact after another .system program has been 
>loaded/executed.

True, but the point is moot, since running a system program,
or any other kind of program, is a "GOTO" and it won't be
returning to the BASIC program anyway.

-michael

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