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https://issues.apache.org/jira/browse/PROTON-1071?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15045930#comment-15045930
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Gordon Sim commented on PROTON-1071:
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{quote}
EventInjector as coded violates Proton's io model: the pipe needs to come from
pn_pipe() and the reading and writing via pn_read() and pn_write(), all on the
reactor's pn_io_t object. It works by fortuitous accident on Posix.
{quote}
I'm not sure I agree. What is your justification for this? The purpose of
pn_selectable_set_fd surely is to associate any file descriptor with the
pn_selectable. Having to use proton io operations defeats what I understood to
be a key purpose of the integration of selectables with the reactor, namely
providing a way to integrate other things into protons reactor event loop.
> EventInjector hangs on Windows
> ------------------------------
>
> Key: PROTON-1071
> URL: https://issues.apache.org/jira/browse/PROTON-1071
> Project: Qpid Proton
> Issue Type: Bug
> Components: proton-c, python-binding
> Affects Versions: 0.11
> Environment: Windows
> Reporter: Ken Giusti
> Assignee: Cliff Jansen
> Fix For: 0.12.0
>
>
> I added a new reactor test that exercises the python-proton ApplicationEvent
> and EventInjector classes:
> proton_tests.reactor.ApplicationEventTest.test_application_events
> See tests/python/proton_tests/reactor.py
> This test passes on linux, but hangs when run on Windows.
> Poking around a bit, I suspect the problem may be in the Windows selector
> code. Description:
> The EventInjector/ApplicationEvent classes provide a way to trigger events
> from threads external to the reactor main loop. See
> proton-c/bindings/python/proton/reactor.py. A pipe is used to wake up the
> reactor when a new event is sent to the reactor (see reactor.py in the python
> bindings). The EventInjector's trigger method puts the event on a queue and
> writes to a pipe to wake up the reactor. The on_selectable_readable callback
> in the EventInjector is called on the reactor thread to get the event off the
> queue and clear the pipe.
> On windows it appears as if the EventInjector selectable is made "readable"
> even though nothing has been written to the pipe. This causes the os.read()
> call in the on_selectable_readable() callback to hang.
> Best I can tell the windows selector code doesn't work properly with a pipe.
> The pn_selector_next() function is returning a read event on the pipe's read
> descriptor even though the pipe is empty. But I'm not familiar with the
> window's selector implementation, so this is a best guess.
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