Adjustment to console signal-handling...
Adjustment to console signal-handling
Do not explicitly interrupt the kernel, because the subprocess
already gets the interrupt. Once we properly prevent this, then
the interrupt can be restored.
Also, the KeyboardInterrupt is still raised if not executing, in order
to restore the prompt.
In ipkernel, the interrupt is ignored during poll, and restored after
the loop exits, to prevent it being swallowed in future code that
expects normal sigint behavior.