Multiple virtual screens on an "X windows" terminal

• US 5,289,574 A
• Filed: 09/17/1990
• Issued: 02/22/1994
• Est. Priority Date: 09/17/1990
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Company (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Sawyer, Jon R.
• Primary Examiner(s): Harkcom, Gary V.
• Assistant Examiner(s): Breene, John E.
• Application Number:
  US07/583,790
• Time in Patent Office: 1,254 Days
• Field of Search: 395/144-161, 395/200, 395/700, 395/163, 340/747, 340/721, 340/723, 340/724, 340/747, 370/85.1
• US Class Current: 715/759
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G06F 3/1423 controlling a plurality of local displays, e.g. CRT and flat panel display

Abstract

A system providing multiple virtual screens that are associated with one or more display elements in a server within an "X Window" system environment. Only the server within this environment has knowledge that the multiple virtual screens are not multiple hardware frame buffers that serve one or more display elements. The user of the server may change from one virtual screen to another virtual screen in various ways. Since the "X Window" client process is unaware that there are multiple virtual screens, the client sends data to a screen assuming that it is a separate "X Window" screen. When this data is received, the server displays the data only if the particular virtual screen is currently selected for display.

Claims

1. A system for displaying a plurality of user selectable virtual screens of data on a single display element, said system comprising:

means for allocating a plurality of buffer descriptions for arranging and storing data, one of said plurality of buffer descriptions being allocated for each of said plurality of virtual screens, each of said buffer descriptions representing one of said plurality of virtual screens, each of said virtual screens containing a plurality of client windows, each of said plurality of client windows representing one or more client processes, wherein each of said plurality of virtual screens supports more than one client process;

means for a user selecting one of said plurality of buffer descriptions for arranging display data; and

means for receiving display data from a client process and using said selected buffer description to arrange said display data on said display element.

2. The system of claim 1 wherein said means for allocating a plurality of buffer descriptions further comprises means for allocating said buffer descriptions on a data storage device as virtual memory.

3. The system of claim 1 wherein said means for selecting one of said plurality of buffer descriptions comprises:

means for determining a location of a cursor on said display element;

means for causing said cursor to move to a new location on said display element; and

means for selecting a different buffer description when said cursor is moved to an edge of said display element.

4. The system of claim 3 wherein said selecting means further comprises:

means for selecting a higher numbered buffer description when said cursor is moved to a right edge of said display element; and

means for selecting a lower numbered buffer description when said cursor is moved to a left edge of said display element.

5. The system of claim 1 wherein the quantity of said plurality of buffer descriptions of user selectable.

6. An "X Window" server system for displaying a plurality of user selectable virtual screens of data on one or more display elements, each having one or more hardware frame buffers, said system comprising:

means for allocating a plurality of buffer descriptions for arranging and storing data, one of said plurality of buffer descriptions being allocated for each of said plurality of virtual screens, each of said buffer descriptions representing one of said plurality of virtual screens, each of said virtual screens containing a plurality of client windows, each of said plurality of client windows representing one or more client processes, wherein each of said plurality of virtual screens supports more than one client process;

means for connecting at least one of said buffer descriptions to each of said hardware frame buffers;

means for a user selecting one of said plurality of buffer descriptions for arranging display data;

means for selecting one of said plurality of hardware frame buffers for displaying display data on one of said display elements; and

means for receiving display data from a client process and using said buffer descriptions to arrange said display data into said selected hardware frame buffer and onto one of said display elements.

7. The system of claim 6 wherein said means for allocating a plurality of buffer descriptions further comprises means for allocating said buffer descriptions on a data storage device as virtual memory.

8. The system of claim 6 wherein said means for selecting one of said plurality of buffer descriptions for display comprises:

means for determining a location of a cursor on said display element;

means for causing said cursor to move to a new location on said display element; and

means for selecting a different buffer description when said cursor is moved to an edge of said display element.

9. The system of claim 8 wherein said selecting means further comprises:

means for selecting a higher numbered buffer description when said cursor is moved to a right edge of said display element; and

means for selecting a lower numbered buffer description when said cursor is moved to a left edge of said display element.

10. The system of claim 6 wherein the quantity of said plurality of buffer descriptions is user selectable.

11. A process for displaying a plurality of user selectable virtual screens of data on a display element, said process comprising the steps of:

allocating a plurality of buffer descriptions for arranging and storing data, one of said plurality of buffer descriptions being allocated for each of said plurality of virtual screens, each of said buffer descriptions representing one of said plurality of virtual screens, each of said virtual screens containing a plurality of client windows, each of said plurality of client windows representing one or more client processes, wherein each of said plurality of virtual screens supports more than one client process;

selecting by a user one of said plurality of buffer descriptions for arranging display data; and

receiving by server software display data from a client process and using said selected buffer description to arrange said display data onto said display element.

12. The process of claim 11 wherein said step of allocating a plurality of buffer descriptions further comprises the step of allocating said buffer descriptions on a data storage device as virtual memory.

13. The process of claim 11 wherein said step of selecting one of said plurality of buffer descriptions for display comprises the steps of:

determining a location of a cursor on said display element;

selecting a different buffer description when said cursor is moved to an edge of said display element.

14. The process of claim 13 wherein said selecting step further comprises the steps of:

selecting a higher numbered buffer description when said cursor is moved to a right edge of said display element; and

selecting a lower numbered buffer description when said cursor is moved to a left edge of said display element.