Re: gnuplot with wxt on MacOS, time for decisions

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Timothée Lecomte wrote:

> 1st solution, as suggested previously = use two processes:
>  - this is the design of the x11 terminal. I don't like it, because I 
> find complicated to have to handle two processes and their 
> inter-communication where we really have one program (one task).

I don't really believe inter-communication between threads to be any 
easier than inter-communication between processes, in the long run. 
More efficient it may be, but it's not easier.  You basically pay for 
the extra speed by extra requirements on careful coding.

> 3rd solution = use one thread only (the most ambitious)
>  - the one and only thread is an event loop.
>  - "a char arrived on stdin" is handled as an event (this is natural, 
> isn't it?), and passed to readline
>  - the event loop is actually the GUI loop, just extended to watch stdin 
> in addition to window events

That's pretty much the way the Windows native terminal has been doing 
things since day 1 (and in a pretty nasty way, too, overriding the 
<stdio.h> functions with macros of our own making).  Which means a bit 
of synergy might be achievable if you go this way.

> Currently, we have:
>     while( readline(); do_line(); ) {};
> 
> Instead we would have an event loop, with the following callbacks:
>     data_is_available_in_stdin() {rl_callback_read_char ();}
>     line_is_completed() {do_line();}

Not necessarily.  It's possible to lace the GUI event handling into the 
readline character input function instead.