User controlled dialog resource switching in a multi-tasking word processor

• US 4,553,202 A
• Filed: 05/06/1982
• Issued: 11/12/1985
• Est. Priority Date: 05/06/1982
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Trufyn, Nicholas
• Primary Examiner(s): Smith, Jerry
• Assistant Examiner(s): Harkcom, Gary V.
• Application Number:
  US06/375,432
• Time in Patent Office: 1,286 Days
• Field of Search: 364/200 MS File, 364/900 MS File
• US Class Current: 710/269
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores

Abstract

User actuates real time resource reallocation in a multi-tasking environment wherein the operating system builds a process queue against a resource and wherein a new task is interrupt invoked with the dispatcher allocating the resource to the next task in the queue, the queue switching being orthogonol to the dispatcher scheduling of processes.

Claims

1. A method for the real time reassignment of input or output means coupling a multi-tasking processor in which switching from task to task is selectively invoked by interrupts including interrupts invoked through the input means, comprising the steps of:

building a linked list of identities of those tasks which call the input or output means and embedding pointers defining a dispatching order there among in counterpart task descriptions; and

responsive to an interrupt invoked through the input means, reassigning the input or output means from the task currently executing to the next task in order on the linked list;

whereby assignment of the input or output means is rotatable among only those tasks in linked list order.

2. A method for real time reassignment of input or output means coupling a multi-tasking word processor in which switching from process to process is selectively invoked by interrupts including interrupts invoked through the input means, comprising the steps of:

forming a queue of processes requiring input or output means and embedding pointers defining the dispatching order among the queued processes in the counterpart process description; and

responsive to an interrupt through the input means, causing a dispatcher to save the state vector of any process currently executing upon the processor in its process description, retrieve a state vector of the next process in the queue in pointer order from the process description of said next process, and transfer control to said next process.

3. A method according to claim 2, wherein the input or output means respectively include a keyboard or display.