[Haskell-cafe] Exiting GLUT application

[Paul L]

Are you trying it on Linux?

I had exactly the same problem. I believe it's with with X11/OpenGL.
I've written C programs using GLUT, freeGLUT and GLFW (another OpenGL
Window Kit) to re-open window after first one is closed. Unfortunately
all gave the same fault. So it leads me to believe the problem is not
really GLUT specific. I've not tried other platforms.

So I ended up using a trick that always keeps the first window and
reuse it for GHCi session. Just hide it and show it would make no
difference to the end user, at least true on both Windows and Linux.
Mac now has a problem prevents getting GLUT event when loaded in GHCi.

Regards,
Paul Liu

On 8/1/07, Dave Tapley <dukedave at gmail.com> wrote:
> Unfortunately whilst the new code is returning me to a 'Main >' prompt
> as required another problem has come up.
>
> The issue here is found when the code is executed in both GHCi (6.6)
> and hugs (20050308).
> Once the code below is loaded evaluating main opens an unfilled window
> as required.
>
> However if this window is closed and main is evaluated again both GHCi
> and hugs die thus:
>
> GHCi: Illegal instruction (core dumped)
> hugs: Unexpected signal
>
> Any thoughts?
>
>
> On 31/07/07, Dave Tapley <dukedave at gmail.com> wrote:
> > Excellent, thank you Marc your advice worked perfectly.
> >
> > For reference the corrected code reads:
> >
> > > import Graphics.UI.GLUT
> > > main = do
> > > getArgsAndInitialize
> > > createWindow ""
> > > actionOnWindowClose $= ContinueExectuion
> > > mainLoop
> >
> > Dave,
> >
> >
> > On 31/07/07, Marc A. Ziegert <coeus at gmx.de> wrote:
> > > in old glut, the main loop was the core of the single threaded program. exiting it did mean to exit the program completely.
> > > in freeglut, you have alternatives. but for compatibility, it defaults to the old behaviour.
> > >
> > > <http://haskell.org/ghc/docs/latest/html/libraries/GLUT/Graphics-UI-GLUT-Begin.html#v%3AExit>
> > >
> > > - marc
> > >
> > >
> > > Am Dienstag, 31. Juli 2007 19:16 schrieb Dave Tapley:
> > > > Hi everyone, I have the following skeleton GLUT code:
> > > >
> > > > > import Graphics.UI.GLUT
> > > > > main = do
> > > > >     getArgsAndInitialize
> > > > >     createWindow ""
> > > > >     mainLoop
> > > >
> > > > It loads into both hugs and ghci fine and when 'main' is evaluated an
> > > > empty window opens as expected.
> > > > However when closing the window (clicking the window manager's x
> > > > button) both hugs and ghci exit with the window, as opposed to
> > > > returning to the the 'Main>' prompt.
> > > >
> > > > I suspect I need some callback to exit the GUI cleanly?
> > > >
> > > > Cheers,
> > > > Dave
> > > > _______________________________________________
> > > > Haskell-Cafe mailing list
> > > > Haskell-Cafe at haskell.org
> > > > http://www.haskell.org/mailman/listinfo/haskell-cafe
> > > >
> > >
> > >
> >
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://www.haskell.org/mailman/listinfo/haskell-cafe
>