Ticket #3529 defect new
closing stdout in a child process on cygwin means that process doesn't receive bytes from stdin anymore. I think.
|Reported by:||zooko||Owned by:||zooko|
When someone runs bin/trial --reactor=select twisted.internet.test.test_process.ProcessTestsBuilder_PollReactor.test_childConnectionLost on cygwin, using the cygwin version of Python, either manually (which I've done on two cygwin installations), or from the twisted buildbot -- http://buildbot.twistedmatrix.com/builders/cygwin-py2.5-select -- then once the child process closes its fd #2, it subsequently receives no further bytes from its fd #1, even though the parent process has written some bytes to that pipe.
I can reproduce this by running the Twisted unit tests, like this:
step 1: get twisted:
svn co svn://svn.twistedmatrix.com/svn/Twisted/trunk twisted
step 2: cd into the top-level directory, and run trial:
cd twisted && python ./bin/trial --reactor=select twisted.internet.test.test_process.ProcessTestsBuilder_PollReactor.test_childConnectionLost
On other platforms that cygwin (see the Twisted buildbot -- http://buildbot.twistedmatrix.com/supported?branch=trunk -- then this test exits quickly with success. On cygwin, using cygwin python.exe, this test instead enter an infinite loop as the child waits to receive further bytes on its stdin, and the parent waits for the child to respond to those bytes. (This doesn't happen on cygwin with the standard Win32 build of python.exe, of course, anymore than it happens on a Windows system without cygwin installed when using that executable.)