Breaking ReadFile() blocking - Named Pipe (Windows API)

Question

To simplify, this is a situation where a NamedPipe SERVER is waiting for a NamedPipe CLIENT to write to the pipe (using WriteFile())

The Windows API that is blocking

Answer 1

Mike,

You can't cancel synchronous ReadFile. But you can switch to asynchronous (overlapped) operations. By doing this, you can implement a pretty scalable architecture.

Possible algorithm (just an idea):

• For each new client call ReadFile
• WaitForMultipleObjects where the handles are overlapped.hEvent + your custom events
• Iterate over signalled events, and schedule them for execution by threads from a threads pool.

This way you can have only few threads to receive connections and read data, while the actual data processing can be done by the threads pool.