Re: using LPVOID
Passing a pointer to integer would require allocating that integer
on the heap.
I don't think it does.
you can easily supply a pointer to a stack based variable to
_beginthreadex or any other function for creating a new thread.
The only limitation I see is that the the stack in which the variable
resides should not be unwound as long as the new
thread is using the pointer.
Right. So now you need some kind of signalling mechanism, e.g. an event,
for the new thread to let the creating thread know that it's now OK to
destroy the variable. That's more elaborate than just allocating it on the
heap.
I already indicated that it is not an ideal situation, but I wanted to point
out
that there is no physical restriction to force you to use heap mem.
One situation I had in the past where stack based pointers were used was in
a program that had to do parallel processing on
input data.
In the main function, I prepared local variables (structs) with input data.
Then I started all threads, passing the pointers to the different local
variables. After that, the main function waited for all threads to finish to
post-process the results.
In such cases, stack based pointers are safe because the synchronization is
done by waiting for the different threads to finish.
Using heap mem also comes with the problem that your thread function has to
use the same heap as the function that starts the thread.
This is no requirement for using the pointer, but if the thread function
does not delete the memory, you have to delete it in the thread that started
the worker thread. In that case you still need signalling betwwen the
threads to determine when it is safe to do so.
--
Kind regards,
Bruno van Dooren
bruno_nos_pam_van_dooren@hotmail.com
Remove only "_nos_pam"