> 2) Has someone tried to make an interface to Qt library ? (it seems Qt > is written in C++ and I do not know if the ISO_C_BINDING can be used > with C++)
Actually, yes. I wrote a (proof of concept for) a Qt-Fortran interface some two years ago. I'd like to continue the project, but didn't so far due to lack of time. It's probably not in a state that you can adopt it without expanding (a lot).
iso_c_binding is sufficient if you write extern "C" interfaces (in C++ code) for all C++ functions that you want to access. (If you want to implement all of Qt, that would be quite some work ...) The Qt data objects are kept opaque and accessed as type(C_PTR). One of the tricky parts is to enable Qt's unique signal/slot mechanism. Qt implements it by a special preprocessor that generates 'invisible' C++ code before compilation. I found a Fortran interface solution that works, but I also use a preprocessor to keep the user code simple (M4).
I took it as a first exercise in OO programming in Fortran; it's possible and convenient to mirror the Qt class hierarchy in a corresponding type hierarchy in Fortran.
> Sincerely yours > Vincent MAGNIN > Institut d'Electronique, de Microélectronique et de Nanotechnologie > France