Communication system for facilitating in full duplex communication mode and without previously defining sessions between sender and receiver programs

• US 5,287,456 A
• Filed: 04/22/1991
• Issued: 02/15/1994
• Est. Priority Date: 10/24/1988
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Rhodes, Murden C., Wang, Jen S.
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): Lim, Krisna
• Application Number:
  US07/698,351
• Time in Patent Office: 1,030 Days
• Field of Search: 395/200, 395/325
• US Class Current: 709/228
• CPC Class Codes: G06F 9/542 Event management; Broadcasting; Multicasting; Notifications
• CPC Class Codes: G06F 9/546 Message passing systems or structures, e.g. queues

Abstract

A method of facilitating program to program communication within memory space managed by a given processor. Would-be sender programs communicate with would-be receiver programs via an intermediate communication facility program acting as a central "post office" for the sender and receivers. Receiver programs identify themselves and their status to the communication facility program by registering their identification and status therewith. Thereafter, any would-be sender programs can send messages or data to any receiver programs which have been defined to the communication facility program much as any post office patron can receive mail addressed to the patron. Senders need not be defined to the communication facility program but need only request delivery of data or a message to a targeted receiver.

Claims

1. In a computer system having an addressable memory, a processor, and a plurality of resident executable processor programs, a method of communicating data in a full duplex mode without previously defining a session between said processor programs from a first of said processor programs acting as a sender to at least a second of said processor programs acting as a receiver, said method comprising the steps of:

storing a communication facility program in said addressable memory;

calling said communication facility program from said second receiver program, said second receiver program identifying both itself and its function as a would-be receiver to said communication facility program;

calling said communication facility program from said first sender processor program in said computer system and delivering simultaneously to said communication facility program data and an indication of a requested function; and

requesting, by said second receiver processor program having said requested function, delivery by said communication facility program of any data for said second receiver processor program.

2. The method of claim 1 further comprising a step of:

copying at said communication facility program said sender program'"'"'s data into address space of said communication facility program allocated for data destined for receiver programs.

3. The method as described in claim 2, further comprising a step of:

notifying by said communication facility program to a said receiver processor program having said requested that data awaits said receiver program in said communication facility program address space.

4. The method as described in claim 3, further comprising steps of:

accessing by said receiver program the address space of said communication facility program and retrieving therefrom data by copying said data into said receive program'"'"'s address space.

5. A method as described in claim 1 or 2 or 3, wherein:

said calling of said communication facility program by a sender or a receiver program includes a call command, the name of the communication facility program being called and a communication parameter specification having fields of information defining the length of the specification and the type of request being presented.

6. A method as described in claim 5, said specification further containing fields of data for the work address of the storage area required for the communication program service module and an identification of the receiver which is destined to receive or which is requesting communication.

7. A method for permitting data transfer in a full duplex mode between a first program and a second program resident in a computer system having an addressable memory and processing means without requiring knowledge by the first program of an address, physical location or active status of the second program, comprising the steps of:

storing a communication facility program in the addressable memory;

registering the second program as a receiver in the communication facility program upon the second program identifying itself and its function as a would-be receiver to the communication facility program;

sending, simultaneously, both data and a function request intended for the second program from the first program to the communication facility program;

storing the data and the request received from the first program by the communication facility program; and

delivering the data and the request intended for the second program to the second program upon a request from the second program, the request to be issued when the second program is active.

8. A method according to claim 7 further comprising the step of:

the communication facility program notifying the second program that the data is available.