The GLX driver first creates an X window using XCreateWindow and initializes GL to use it.
Window parameters set in the configuration file can be used with this type of driver.
This driver can use a window created by the application ( see SET X-WINDOW IDENTIFIER)
For compatibility with previous releases another driver can be used:
7176 opens a window by calling the GL function winopen. This driver cannot use an existing X or MOTIF window. This driver is accepted for compatibility with older versions and will be removed from the driver list in future releases of GPHIGS.