Description
@anntzer @tacaswell
Hi! I have just tested the master branch on Windows and found that there is indeed a problem with the QSocketNotifier (it appeared here: #13306 (comment)). Previously, on that Windows machine, I was running my old code with QAbstractSocket which was fine, and did not test the newest version with QSocketNotifier there (my fault, sorry). I have tested on Linux, and there is no such problem there.
The code to reproduce on Windows (in Jupyter):
%matplotlib qt
from matplotlib import pyplot as plt
plt.plot([1,2])
plt.pause(.1)
plt.pause(.1)
plt.pause(.1)The problem seems to be that if socketpair generates a socket with the same fileno value as it generated in the previous pause() call, the QSocketNotifier unexpectedly fires and hangs here:
because nothing was actually written to the
wakeup_fd. I don't understand how that can be.
Workaround fix:
rsock.set_blocking(False)
@sn.activated.connect
def on_signal(*args):
try:
signal = rsock.recv(1) # clear the socket to re-arm the notifier
except BlockingIOError:
pass # false-trigger, nothing on rsockWhat should we do with this? Is there a better solution?
Originally posted by @vdrhtc in #13306 (comment)