Re: 4.0 release goals

[Ben Abbott]

On Nov 4, 2012, at 5:43 PM, Ben Abbott wrote:

> 
> On Nov 1, 2012, at 12:59 PM, Jordi Gutiérrez Hermoso wrote:
> 
>> I would like to propose some rather ambitious goals for 4.0, and I
>> think we should be bold enough to use a major version number.
>> 
>> In case you missed it in the help list, there's an interesting thread
>> about the GUI. Israel Herraiz forked it and stabilised it:
>> 
>>   
>> http://octave.1599824.n4.nabble.com/When-will-the-new-GUI-be-ready-tp4645798p4645846.html
>> 
>> I would like to prioritise getting the GUI stabilised so we can start
>> contemplating making a release. I think our 4.0 release goals should
>> be:
>> 
>>   - fltk enabled by default
>>   - Stable GUI
>>   - JIT compiling working
>>   - Windows and Mac OS X binaries
>> 
>> We're already made many inroads into many of these goals. What do you
>> guys think, can we do it?
>> 
>> - Jordi G. H.
> 
> Since the gui build process was integrated into the CLI build process, the 
> gui has not run under MacOS X.  I'm not certain, but I think gnuplot had a 
> similar problem.
> 
>       http://www.digipedia.pl/usenet/thread/12789/10528/#post10548
> 
> When I try to run the gui, I get the error below (repeated 16 times).  Which 
> is the same error encountered by the gnuplot developers.
> 
> The process has forked and you cannot use this CoreFoundation functionality 
> safely. You MUST exec().
> Break on 
> __THE_PROCESS_HAS_FORKED_AND_YOU_CANNOT_USE_THIS_COREFOUNDATION_FUNCTIONALITY___YOU_MUST_EXEC__()
>  to debug.
> 
> Fixing this is beyond my abilities. but I can test patches.
> 
> Ben
> 

I emailed Ethan Merrit (gnuplot development) and got the respone below.

On Nov 4, 2012, at 6:16 PM, Ethan Merritt wrote:

> On Sunday, 04 November 2012, you wrote:
>> Ethan,
>> 
>> Octave's developers are planning to introduce a Qt based GUI/IDE soon.  At 
>> the moment it does not run on MacOS.  I'm not intimately involved in that 
>> development, but have the impression that Gnuplot had a similar problem with 
>> its Qt terminal.
>> 
>> Octave's GUI/IDE did run on MacOS X when it was compiled independently, but 
>> since theGUI/IDE was integrated into the CLI code base it no longer runs.  
>> Instead we get the errors below.
>> 
>> The process has forked and you cannot use this CoreFoundation functionality 
>> safely. You MUST exec().
>> Break on 
>> __THE_PROCESS_HAS_FORKED_AND_YOU_CANNOT_USE_THIS_COREFOUNDATION_FUNCTIONALITY___YOU_MUST_EXEC__()
>>  to debug.
>> Do you know the details of what was needed to get the Gnuplot qt terminal to 
>> run?  Or, can you point me to some one who does?
> 
> Yes.  
> OSX apparently has two hard restrictions that both seem overly severe
> to people familiar with normal [li/u]nix practice:
> 
> 1) As the message states, the only legal operation after forking is to 
> immediately
>   exec().  Well, I don't know how "immediate" that is, but certainly you 
> cannot
>   execute standard library calls before exec().
> 2) The event loop for writing to the graphics library must be in the main 
> process,
>   it cannot be in a separate thread or child process.
> 
>> I'm looking for is a simple high level description of what the problem was 
>> and how it was fixed.
> 
> So the fix, if you can call it that, is to write a separate program that
> executes the graphics commands.  The main process then does fork() + exec() to
> run that separate process, and communicates via a pipe.
> 
> In gnuplot's case, the relevant bits of qtterminal are built into
> a separate executable gnuplot_qt that acts as an outboard driver
> analagous to gnuplot_x11.  Both manage the graphics output in response
> to commands piped from gnuplot proper.
> 
>       Ethan

Ben