I get no value for videoInfo->vfmt->BytesPerPixel

SDL Development
1

In my code I try to do

    const SDL_VideoInfo* videoInfo;
    videoInfo = SDL_GetVideoInfo();
    std::cout<<"pixlar "<<videoInfo->vfmt->BytesPerPixel<<std::endl;
    std::cout<<videoInfo->current_w;

and I get priting of

pixlar
1600

while running 1600x1200 resolution.
But I get no value for BytesPerPixel.
I run this code before calling SDL_SetVideoMode.
Shouldn’t I then get a value or have I missed something important here?