Howdy. I've prepared a testcase for a bug or inconsistency with linux that is affecting one of my projects.
Basically I have a background process that keeps some state always running with a pipe open for reading requests. Foreground processes that try to open that pipe for writting (to send a request) then block/fail on the second and subsequent tries. The whole setup can be simplified with a small testcase that runs in a single process. https://github.com/joaoe/cygwin-pipe-testcase I left a README that explains things in a bit more detail. To summarize here, consider the following order of events: * open pipe for reading with NONBLOCK into FD1 -> OK * poll() FD1 -> empty event list, OK * read from FD1 -> zero length read, OK * open pipe for writting into FD2, write something -> OK * poll() FD1 -> POLLIN and POLLPRI, POLLPRI is unexpected here, FAIL * read from FD1 -> got stuff that was written * close FD2 * poll() FD1 -> POLLIN and POLLPRI, wrong, should report POLLHUP, FAIL * read from FD1 -> zero length read, OK * open pipe for writting into FD2 again -> got error ENXIO, FAIL So, known bug ? Do you confirm my observations ? Any pointers so I could perhaps look into the relevant code ? It seems like Cygwin still keeps some dirty state somewhere that tells the pipe is still open by a writer somewhere. Thank you ! -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
