Display adapter interface layer

A method of interfacing between a plurality of application programs and a plurality of display adapters, each of said display adapters having a plurality of functions for supporting a display, the method comprising the steps of:

• a) providing a first interface from a first one of said application programs to functions of a first display adapter;
• b) providing a second interface from a second one of said application programs to functions of said first display adapter;
• c) providing a fourth interface from said first application program to functions of a second display adapter;
• d) providing a fifth interface from said second application program to functions of said second display adapter;
• and
• e) providing a third interface from all of said application programs to less than all functions of said first display adapter and providing a sixth interface from all of said application programs to less than all functions of said second display adapter such that some functions of the second display adapter are not accessible by the application programs through the sixth interface.

A data processing system comprising:

• a) a first display adapter having functions for supporting a first display and a second display adapter, each display adapter having a plurality of functions for supporting a second display;
• and
• b) a host computer including:
• i) first and second application programs;
• ii) first driver means providing a first interface from said first application program to functions of said first display adapter;
• iii) second driver means providing a second interface from said second application programs to functions of said first display adapter;
• and
• iv) third driver means providing a fourth interface from said first application program to functions of said second display adapter;
• v) fourth driver means providing a fifth interface from said second application program to functions of said second display adapter;
• and
• vi) access means, coupled to each said driver means and to each said display adapter, for providing a third interface from all of said application programs to less than all functions of said first display adapter, and for providing a sixth interface from all of said application programs to less than all functions of said second display adapter such that some functions of the second display adapter are not accessible by the application programs through the sixth interface.