On Thu, Feb 6, 2014 at 8:33 AM, DASDBILL2 <[email protected]> wrote:

> I have written oodles of code that scan TIOTs, which almost always ran in
> "key eight", and I never got a S0C4 in that code, so I cannot believe that
> the TIOT is allocated in "key one" storage.  I would believe "key zero."
>
> Bill Fairchild
>
>
>
>
Bill,
According to the PoPS, a program running with a PSW key of "n" can read
storage in key "m" (n != m) unless the storage is "fetch protected". Key 0
storage is "nothing special" in regards to being "universally readable".
PSW key 0 is special, of course. So a key 8 program can read the TIOT in
key 1 (if indeed it is, I don't assert of my own knowledge) unless the TIOT
storage were marked "fetch protected".

-- 
Wasn't there something about a PASCAL programmer knowing the value of
everything and the Wirth of nothing?

Maranatha! <><
John McKown

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