The book “OpenGL programming guide: the official guide to learning opengl, version 4.3” claims in page 847:
But when I add the code
int nnn=glGetIntegerv(GL_NUM_EXTENSIONS);
, expecting I can be returned number of extensions, I got nothing but a lot of errors. I referred to MSDN document here: glGetIntegerv function (Gl.h) - Win32 apps | Microsoft Learn, but found that there is no GL_NUM_EXTENSIONS token supported. Is the author kidding me? If not, how to access OpenGL Extensions under Windows (using so-called glGetIntegerv or not)? Thank you.