vrdp + rdesktop missing screen updates

[tschoenemann]

Since Virtualbox 4.0 i see a strange rdp bug, which didnt exists in Virtualbox 3.2
It seems that screen updates which occur while your vm window is hidden (for example minimized or you switched to another desktop) are not applied when you restore the vm window.

Example to reproduce:
Start a VM of your choice with VBoxHeadless, open a terminal window.
Now you need a commandline program which needs some time to finish. start it, minimize your vm window, restore the window after the time you guess the execution of the program finished.
Now you see that the output of that program in your terminal window is garabage. You need to click inside or press enter to get the screen finally updated.

I made my test with a short script:

echo "START"
sleep 2
echo "garbage garbage"

During the "sleep 2" you have to minimize the vm window.

This missing update also is to be seen with gui applications.

I tested with different guests (win,os2,linux) and hosts (sol10, sol11) and found out that this error *only* disappears if you downgrade to virtualbox 3.2

I used the solaris11-rdesktop , the opencsw rdesktop and the rdesktop-vrdp which comes with Virtualbox.

If you use the VirtualBox GUI or VBoxSDL this does NOT happen, so its the VRDP + rdesktop combination.

[tschoenemann]

In rdp-1.png you see the "garbage" output after minimizing+restoring, marked with red circle In rdp-2.png you see the same, without minimizing+restoring, no "garbage" The ts-20107.xml + VBox.log are from the example os2-VM

[Frank Mehnert]

We found one potential problem which seems to affect only rdesktop clients. Could you check if ​this extension pack fixes the redraw problems? Just install this extpack as replacement for the 4.1.14 one.

[tschoenemann]

Replying to frank:

We found one potential problem which seems to affect only rdesktop clients. Could you check if ​this extension pack fixes the redraw problems? Just install this extpack as replacement for the 4.1.14 one.

The fix works!

[Frank Mehnert]

Fix is part of VirtualBox 4.1.16.