A Stupid question about OpenGL Version

I am using Microsoft OpenGL. The developing environment is Microsoft Visual Studio.net 2003. From the header files of OpenGL I can read BUILD Version: 0004. But how can I get to know the version of OpenGL I am currently using? Thanks!

printf("OpenGL Version : %s
", glGetString(GL_VERSION));
printf("OpenGL Vendor : %s
", glGetString(GL_VENDOR));
printf("OpenGL Renderer : %s
", glGetString(GL_RENDERER));

Thanks a lot!