🚀 go-pugleaf

There is a bug in SNAPSHOT.ACC which makes it impossible to take pictures of
a GEMDRAW or EASYDRAW screen.
If you use Snapshot/0.14 with resident GDOS.PRG, you only get "empty" pictures.
This is especially annoying as the double WORDPLUS - EASYDRAW would have been
an excellent documentation system.
Last weekend I found the reason for the "empty" pictures.
It is a call of the VDI copy raster routine (vro_cpyfm) with a handle being
constantly 1. This works if the screen is the only VDI device.
But with GDOS you can have other VDI devices and the physical device handle
number of the screen has changed.
If someone is interested in my modified version of SNAPSHOT, I will post it.

Concerning VDI devices I have a few questions to which someone perhaps has
answers:

1) Is the physical device handle number identical to the device identification
   number used as input for the open workstation call ?

2) How can I see, which workstation is opened ?

3) Who opened the screen workstation first and which device id number is used ?

4) Why does the ASSIGN.SYS for EASYDRAW use 4 device id numbers for the screen ?


Thanks in advance.

  Konrad Hahn @ University Darmstadt
  BITNET: XBR4D76H@DDATHD21