Loading drivers and the shell

  • Thread starter Thread starter Damon Gautama
  • Start date Start date
D

Damon Gautama

Hello,
It has fallen in my lap to research a potential problem in our XPE
configuration. This is my first time exploring this realm, so please excuse
any untoward display of ignorance.

The requirement is to boot up into our custom application without giving the
user a chance to monkey with anything in the mean time. An attempt, before
my time, to launch without Explorer caused application failure due to
drivers not being loaded. From what I have read so far, I don't think there
is an particular relationship between the shell and drivers, so my guess is
that launching Explorer just happens to give the drivers time to load before
our app is called.

Does this sound right? Could I just write a shell that was essentially
::Sleep(5000); ::CreateProcess(<our exe>)? Could I then launch Explorer
later if needed?

Am I on the right track, or am I barking up the wrong tree (what's a
sentence without multiple metaphors?).

Thanks for any and all help,
damon
 
I don't know what drivers your application is using, but Sleep(5000) is not
a good solution. Why not 4000 or 6000?

Instead find and read info on function CMP_WaitNoPendingInstallEvents



Regards,

Slobodan
 
Hello,
It has fallen in my lap to research a potential problem in our XPE
configuration. This is my first time exploring this realm, so please excuse
any untoward display of ignorance.

The requirement is to boot up into our custom application without giving the
user a chance to monkey with anything in the mean time. An attempt, before
my time, to launch without Explorer caused application failure due to
drivers not being loaded. From what I have read so far, I don't think there
is an particular relationship between the shell and drivers, so my guess is
that launching Explorer just happens to give the drivers time to load before
our app is called.

Does this sound right? Could I just write a shell that was essentially
::Sleep(5000); ::CreateProcess(<our exe>)? Could I then launch Explorer
later if needed?

Am I on the right track, or am I barking up the wrong tree (what's a
sentence without multiple metaphors?).

Thanks for any and all help,
damon
Click to expand...

I had the same problem with my application (DirectX): if it is started too
soon, DirectX display initialization fails.

It takes about 15 seconds (in my case) after the shell is started before
the display becomes available.

When another (non-directX) app runs as shell it also only appears on screen
some time after it's been started, but it looks like XPE intercepts the
problem in this case.


To minimize the amount of changes to my application, I modified it so it
just stops with a certain exit code if DirectX init fails; then I wrote a
launcher app that's started as shell instead.
The launcher starts the main app, goes into a WaitForSingleObject until it
exits, and depending on the exit code it stops itself too or it retries
starting the main app. I included a five second Sleep() before each retry.

A retry loop around the initialization in my original app would have been a
more elegant solution, but it didn't work on the first attempt and I didn't
feel like debugging DirectX code on the target platform ;-)
 
Thanks for the idea. I think we are going to try the
CMP_WaitNoPendingInstallEvents route. If that doesn't work, we'll try to
mimic your workaround.

damon
 
Back
Top