External classes for writing to Omnis 7 DF

[Dario Greggio]

Hi Geir,
I seemed to remember that possibility, and I checked now into the 
Include file that I was (and still am at times) using to write Externals 
for Omnis 7:

I can see this
pascal OBOOL _DoPrepare(short pfu,OPROC callback) = 
{0x303C,0x000C,0x2057,0x4E90};
pascal OBOOL _DoUpdate(OPROC callback) = {0x303C,0x000D,0x2057,0x4E90};

among the other declarations, so definitely it would look like an Update 
is doable (I never did that, but did many other things :) )

As for data corruption, I might think that this would go the same path 
as standard Omnis code, so there should be no special problems...