These procedures can be used to check the OpenGL version and supported extensions. Note that these, too, should only be called when an OpenGL context is active!
Returns the OpenGL version, as a list of exact integers. For example, version 3.1.2 would return a list (3 1 2).
Returns the supported OpenGL extensions, as a set of symbols.
Checks whether the given extension is supported.
Checks if the OpenGL version is at least the given version.
Returns #t if v is an OpenGL sync object, #f otherwise.