🚀 go-pugleaf

In article <1993Jan4.205811.107@actrix.gen.nz> Dennis.Ingram@bbs.actrix.gen.nz writes:
>As I understand it, in order for a thread to use WinSendMsg it must
>have a message queue.  I have always wondered what is the best thing
>to do when you have multiple threads that need to access a window - do
>you use WinPostMsg and block using semaphores, or define a queue and
>use WinSendMsg?  What is the overhead of defining a message queue (in
>terms of system resources), bearing in mind that the queue is only
>there to allow WinSendMsg access?

Well, it depends.  If the calling threads are yours -- you created them --
then I think creating a message queue is the simplest thing to do.  Don't
forget that you can limit the size of the queue to something small if
you're not going to be creating any windows.  Why not let PM do all the
synchronization work for you?

The WinPostMsg/semaphore method must be used if you're being called by
a thread that you didn't create, because then you can't reliably create
a message queue.  The PM docs state that creating a message queue should
only be done at most once per thread, and I have not found any way to
check for the existance of a message queue (if anyone knows, please tell me!).
This method definitely takes more work because you have to allocate
the semaphore and pass it to the other thread...

-- 
 Eric Giguere                                    giguere@csg.UWaterloo.CA
          So is Windows NT short for "Windows, NOT?"