Thanks Jasen! I was unsure which function could make the job. Though I tried
to cause a fault with the function 21h/49 by running it single step and 
started another program using the _same_ segment. At my surprise there was no
conflict at all. I wrote say at 17D5:0000 EE and in the another window 
17D5:0000 00 none of values changed the other. Looks like multitasker are
really bugs aware :-)
--- Drink or Die
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