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Error in XMS specification? (Developers)

posted by ecm  , Düsseldorf, Germany, 27.04.2019, 16:16

While working on my symsnip collection, I encountered an error.

XMS 2.00 http://www.phatcode.net/res/219/files/xms20.txt

XMS 3.00 http://www.phatcode.net/res/219/files/xms30.txt

In the section titled "Move Extended Memory Block (Function 0Bh)" it reads:

> If the source and destination blocks overlap, only forward moves (i.e. where the source base is less than the destination base) are guaranteed to work properly.

RBIL 61 in the Int2F.4310 description of XMS functions also has wording to this effect.

The error is that forward moves (DF=UP, cld) work properly on overlapping destination and source when the *destination* is below the source. This is the other way around than what the specification lists. From what I can tell, drivers actually implement the forwards movement.

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Complete thread:

• Error in XMS specification? - ecm, 27.04.2019, 16:16 (Developers)
  • Error in XMS specification? - Oso2k, 27.04.2019, 20:20
    • Error in XMS specification? - ecm, 27.04.2019, 21:40