I am on OSX. I am importing opencv-python, so it might help; however, I am not showing anything, it's all command line off-screen processing.
While True:
   do work .... 
   key = cv2.waitKey(1)
   print key
The call to cv2.waitKey(1) consistently returns -1.
If I call cv2.imshow(..) before it, then it behaves correctly.
However, I have nothing to show, any chance I can still detect a keypress?
I need a keypress which isn't ctrl+c
