Using GTK+ on Mac OS X 3 GTK Library Using GTK+ on Mac OS X OS X-specific aspects of using GTK+ The Mac OS X port of GTK+ is an implementation of GDK (and therefore GTK+) on top of the Quarz API. Currently, the Mac OS X port does not use any additional commandline options or environment variables. For up-to-date information about the current status of this port, see the project page.