I think in that case you need to pass an instance of FFIExternalValueHolder.
On 7 April 2016 at 17:42, Thibault Raffaillac <thibault.raffail...@inria.fr> wrote: > Hi again, > > Does anyone know what is the state of return by reference in FFI? > Example: > glGetAttribute: attr into: value > <primitive: #primitiveNativeCall module: #NativeBoostPlugin error: > errorCode> > ^ self nbCall: #( int SDL_GL_GetAttribute(SDL_GLattr attr, int > *value) ) > > On my image (50666) it does nothing on value yet (if nil, remains nil, if > SmallInteger 0, remains 0). > (SDL2 glGetAttribute: 6 into: value) should return 16. > I've seen NBOpenGL put "out" before value in method header, should it > matter? (does not make it work though) > Last but not least, should we attach '*' to the type or variable for FFI > to understand it is a pointer? > > Cheers, > Thibault Raffaillac > >
