There's a well-known algorithm that employs readers/writer lock synchronization between threads of a single process on a Windows platform using pure WinAPIs/C++:
http://www.glennslayden.com/code/win...er-writer-lock

In my case I need to do this between several processes, i.e. the writer is in one process, and readers are in other processes. Any idea how to do that?

PS. I need this for an already developed project, so I can't use anything other than C++/MFC or pure WinAPIs. In other words I can't use Boost or the like extensions.