Re: SIGIO and the NS port

[Paul Eggert <eggert@cs.ucla.edu>]

Alan Third wrote:
> I’ve stopped the signal handler from responding to SIGIO,

I'm not following, as sigaction (SIGIO, ...) is still being called, so the 
signal handler deliver_input_available_signal is still responding to SIGIO, and 
is setting pending_signals to true.

The changes you made affect SIGUSR1 and SIGUSR2 handling, since they patch 
handle_user_signal: they cause the SIGUSR1 and SIGUSR2 handler to not process 
SIGIO events. Also, they prevent SIGIO from being masked out during non-SIGIO 
signal handlers. Is that what you intended? I'm not getting the connection 
between these non-SIGIO handlers and interrupt_input.

> and the two
> places where the NS GUI used to raise SIGIO have been replaced with
> direct calls to the SIGIO handler code.

That sounds like a reasonable thing to do in any event. I don't see why the code 
needs to do a raise (SIGIO) when it can do a handle_input_available_signal (SIGIO);