Re: [Gtk2hs-users] Some really ugly code... (threading again)

[Axel S. <A....@ke...>]

On 14 May 2004, at 15:05, Duncan Coutts wrote:

> On Fri, 2004-05-14 at 09:13, Axel Simon wrote:
>> On 12 May 2004, at 20:29, Duncan Coutts wrote:
>>> The attached code does a similar thing but in the other direction, it
>>> installs ghc's event loop into gtk's event loop.
>
>> Hm, ok, that is definitely a nice hack. However if this will not work
>> with a threaded GHC, then I guess it's a no-go. I think it can be
>> assumed that threaded RTS will be the standard in the future.
>
> It would work only if we can bind all Haskell threads that want to
> access the GUI to the OS thread that is running gtk_main.
>
> It would need an extension of the bound threads API to specify which OS
> thread to bind to so you can bind to a existing OS thread. Wolfgang is
> sceptical of this however, so this probably is a no-go.
>
> When people eventually get a high-level Haskell gui API, there might be
> more pressure for a solution, since several high-level designs I've 
> seen
> make heavy use of threads and it would be too great a burden to think
> about locking.
>
Maybe we've approached the problem from the wrong end. Basically, we 
should make the user run gtkMain in the main thread which will block. 
If the user forks of a process before the call to gktMain, then all 
accesses to the GUI library in all forked processes must be protected 
by the locking function. I think this rule is not too complicated and 
is kind of intuitive. What do you think?

Axel.