Multithreaded CLX: queue-event and wait-for-event

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Suppose two threads (processes, to use the lispm-speak) A and B.  A is
running an event loop, so calls process-event or some related public
function.  According to my reading of input.lisp, process-event
eventually calls wait-for-event, which calls buffer-input-wait, which
calls buffer-input-wait-default, which blocks (or pseudo-blocks, if
you have userland threads) waiting for input on a file descriptor.

If thread B calls queue-event to add to the event queue while A is
blocked waiting for network input, A will not notice this - it just
continues waiting.  Is this correct?  Intentional?  Desirable?

The context: I'm looking at read-input with a view to making it use
thread synchronisation stuff that we have a reasonable hope of
implementing efficently on a native (OS) threaded system.  The above
came to light while reading through input.lisp to work out what it
does.

Any input welcome.


- -dan

- -- 

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