Re: GTK with libdispatch (GCD) on Linux and X11

[Hrvoje Niksic <hrvoje niksic avl com>]

On 05/03/2016 03:26 PM, Integratron wrote:
> This is great feedback! My application is very simple - it will only
> have buttons, checkboxes and a graphics area for showing monitoring
> information from a running application. There will be no file chooser,
> or modal dialogs. (It is easy to imagine these types of widgets creeping
> in.)

GTK almost certainly uses timeouts internally. For example, GTK button 
has a 200ms timeout before painting itself depressed, for a more 
appealing appearance. Menus have timeouts. It is my understanding that 
GTK 3 has more support for various animations, which are on the event 
loop level almost certainly implemented in terms of timeouts.

> I wonder, however, if there might be a "Simple GTK Subset" that is
> safe to use in the manner I outlined. What do you think? Would it be a
> useful subset?

Even if such a subset existed at this point, it would not be safe 
against trivial changes in the implementation.

The separate-thread-event-loop approach, on the other hand, should be 
robust and straightforward to implement.

> Fundamentally, GTK is based on an event-loop waiting on a poll, and
> libdispatch unravels the poll into individual callbacks for each
> event source.  It may turn out to be that these two aren't very
> compatible.

If they are polling on different things, you shouldn't care. GTK will 
take care of the X11 socket and its own timeouts and queue of idle 
callbacks, and libdispatch will take care of everything else.

Hrvoje