Hi Mark,

>What is your preferred technique for synchronizing access to the shared memory? Do you use a a mutex, or do you prefer to use the VFP SYS() critical section function?...

I use MUTEXes. However, it looks like waiting for a mutex takes away the CPU from the current thread and puts it into a wait state even when a MUTEX is available. Last time I tested this, waiting for a MUTEX took up to 10 ms which quickly accumulates in a loop. You might want to test performance on your system.

I haven't verified this, but my assumption is that VFP only uses one critical section object for its SYS() function. That means, you can't fine tune access to different shared memory blocks or features thereby loosing scalability. If that's not an issue for you, a critical section might actually be easier and faster than using a MUTEX.