[SDL] [Need help] Why this code crached?

[David Olofson]

On Saturday 20 January 2007 21:57, Igor Mironchick wrote:
> 2007/1/20, David Olofson <david at olofson.net>:
> >
> > On Saturday 20 January 2007 21:07, Igor Mironchick wrote:
> > [...]
> > >     static void audio_callback( void *userdata, Uint8 *stream,
> > >                                       int [...] len );
> > [...]
> >
> > You can't pass this function as a C callback! It needs
> > an "invisible" 'this' argument to work.
> >
> > You need to use a C calling convension wrapper callback, that
> > casts 'userdata' to the type of your class, and then forwards the
> > call to your audio_callback().
> 
> 
> Ooops, and where I can read about "C calling convension wrapper
> callback"?

I think this has been discussed a few times in the past. It's a 
standard solution for wiring C API callbacks to non static C++ class 
members. Handy when you need to keep track of multiple instances of 
things in a mixed C/C++ system.

Either way, as you're using a static member here, this shouldn't be an 
issue. I should learn to read. :-D


//David Olofson - Programmer, Composer, Open Source Advocate

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