Console app window lockup

[Doug Gordon]

For historical reasons, our main app that runs on XPE is a "Console
application" that does its display using a console window that we update
with the standard Win32 console API. Under conditions that are impossible
for us to reproduce at our facility, our customer is experiencing situations
in the field where the application's window "locks up" and no longer
updates. It is not a screen lockup, as other operations can still be done on
the PC.

It is also not an application lockup, as the application continues to run
just fine and do its job, but with its window "frozen". The cause for this
has been driving me nuts. The way the application is written, it has to be
running its normal processing loop, which means it goes through the
functions that make the Win32 calls to update the console window. So
apparently the app has no idea that its window is not updating, and it just
goes on its merry way. And I can't figure out any way that a bug in my app
could be causing this type of problem; most screwups like stack or memory
corruption would lead to a crash -- not these symptoms.

After doing some research, I recalled that the Windows process "csrss.exe"
("Client/Server Runtime Server") is directly involved in managing console
windows. Has anyone heard of any problems related to this module? Any other
ideas??

-- Doug G

 

[KM]

Doug,

I never heard of console lockup issues on XPe. But I believe that it is
possible to get the console UI locked if the corresponding message loop gets
stuck processing a message.
WIthout seeing the code it is hard to guess what might be wrong there.

Have you tried moving the message loop in to a separate thread? (certainly
with proper app object synchronization and etc.)

Also, if you are not able to repro the issue on your side but your
customer(s) can, perhaps you may want to add an extensive logging to a file
(from the message loop to all the message handler and etc.) so that you can
debug the issue by looking at the logs. Usually laborous process but worth a
try when you can't work on the issue in dev environment.

Regards,
KM

 

[Matt Kellner \(MSFT\)]

I wonder if it's possible that this is a display driver issue? That's about
all I can think of, other than what's already been suggested.