Example of test_connect_eintr3.py output on OpenIndiana:

Register SIGINT
Register SIGALRM
Register SIGWINCH
Register SIGTERM
Register SIGCHLD
Send SIGALRM every 200.0 ms
Run func() during 5.0 seconds
Type CTRL+c, resize the window, etc.

______[]____[]_____[******]______[]_______[*****]______[*****]______[]

Test completed in 5.2 sec
func() has been called 7 times
Got 56 signals
Got 16 signals during connect()


Oh, and obviously, test_connect_eintr3.py fails with InterruptedError without the patch. Example on Linux:

Register SIGINT
Register SIGALRM
Register SIGWINCH
Register SIGTERM
Register SIGCHLD
Send SIGALRM every 200.0 ms
Run func() during 5.0 seconds
Type CTRL+c, resize the window, etc.

[]____[]_____[]_____[]____[******Traceback (most recent call last):
  File "test_connect_eintr.py", line 97, in <module>
    func()
  File "test_connect_eintr.py", line 51, in func
    client.connect(server_addr)
InterruptedError: [Errno 4] Interrupted system call