Coroutine awakened on failed connect, but error status not propagated (connect appears successful)

[resetius]

When attempting to connect to a port where no server is listening, the poller (e.g., kqueue) returns an error event (such as EV_EOF). However, the coroutine waiting for the connect is resumed without propagating the error status. As a result, the coroutine incorrectly assumes that the connection was established successfully, even though the connect actually failed. The error from the poller should be checked and properly reported to the coroutine

[resetius]

Workaround: Immediately after connect, perform a write to the socket (for example, send a test message in your protocol). This will reliably trigger an error if the connection was not actually established