seems to me that sending 2 Setting them both and getting rc=success for both should be almost as good as checking afterward.
The driver should have send a checkstatus or failure if it didn’t like the set. But it never hurts to recheck that the Set operation was successfully by followin git up with a Get to make sure.
the first thing that catches my eye is the twCapability class definition.
I don’t think this definition will work for come of the caps
hContainer = Twain.GlobalAlloc( 0x42, 6 );
the second parameter, the 6, isn’t always going to be 6. I don’t think 6 is correct here. Seems that for a bool inside a oneVal this should be 4 (but some mornings I can’t count to 6 without taking off my socks so double check before you take my word for it). I don’t think this is why your deplex code doesn’t return 2 images, just that in other cases your 6 won’t be big enough – frame and string values won’t fix.
But then why aren’t you getting more images back..?
What is the name of the device you’re using?
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