<mode> may either be GLX_3DFX_WINDOW_MODE_MESA to indicate window
rendering or GLX_3DFX_FULLSCREEN_MODE_MESA to indicate full-screen mode.
<mode> may either be GLX_3DFX_WINDOW_MODE_MESA to indicate window
rendering or GLX_3DFX_FULLSCREEN_MODE_MESA to indicate full-screen mode.