Re: Yet another GUI releated thought

[John Swensen]

On May 12, 2008, at 11:19 PM, Ryan Rusaw wrote:

> On Mon, May 12, 2008 at 9:29 PM, John W. Eaton  
> <address@hidden> wrote:
> > On  9-May-2008, Przemek Klosowski wrote:
> >
> > | Now, a somehow ugly compromise might be to introduce  
> > synchronization
> > | points, either implicit in the octave eval loop or explicit in user
> > | code (process_gui_callbacks())
> >
> > I think that's what John Swensen's IDE does now.
> >
> > jwe
>
> Would it not be possible to allow the various IDE's to register code
> to be called on each iteration of the octave eval loop at startup?
> Then leave it to each IDE development team to determine what
> functionality they need themselves ie. updating a variable watch
> window in the IDE via a data socket or other IPC mechanism.
>
> Ryan

This mechanism is already in place.  A while back John Eaton cleaned  
up my patch to allow multiple "clients" to register for the Readline  
idle event.  I currently have a class  sources for my IDE called  
octave_server that is a singleton and registers a function with this  
idle loop.  Whenever the function is called, there is a transaction  
between the server class and octave (gets new history items, gets a  
table of whos-like variable information, processes breakpoint  
additions and hits, requests variables, etc). Then the IDE is free to  
query these values from the octave_server class whenever it feels like  
it.  Since the data in the octave_server class is mutex protected, and  
we can guarantee that the octave_server class only interacts with  
Octave while the octave interpreter is in the Readline idle loop (e.g.  
nothing is being executed), then this is as much "thread-safety" as  
most IDE's will need.

John Swensen