Browse Prior Art Database

Technique for Processing Exchange Diskettes on the IBM Series/1 Event Driven Executive

IP.com Disclosure Number: IPCOM000050457D
Original Publication Date: 1982-Oct-01
Included in the Prior Art Database: 2005-Feb-10
Document File: 3 page(s) / 15K

Publishing Venue

IBM

Related People

Newmark, CA: AUTHOR

Abstract

A technique is described which allows exchange diskette data sets to be read and written by application programs running under the IBM Series/1 Event Driven Executive (EDX) system. The application program is allowed to process exchange data sets in the same manner that EDX data sets are processed. The concepts and facilities of the Event Driven Executive system are described in the System Guide SC34-1702. Also of interest is the EDX Internal Design Guide LY34-0212. Additional diskette details may be found in the IBM Diskette General Information Manual GA21-9182. The application program "opens" the exchange data set using this technique. Subsequent operations are performed using conventional EDX diskette input and output operations.

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Technique for Processing Exchange Diskettes on the IBM Series/1 Event Driven Executive

A technique is described which allows exchange diskette data sets to be read and written by application programs running under the IBM Series/1 Event Driven Executive (EDX) system. The application program is allowed to process exchange data sets in the same manner that EDX data sets are processed. The concepts and facilities of the Event Driven Executive system are described in the System Guide SC34-1702. Also of interest is the EDX Internal Design Guide LY34-0212. Additional diskette details may be found in the IBM Diskette General Information Manual GA21-9182. The application program "opens" the exchange data set using this technique. Subsequent operations are performed using conventional EDX diskette input and output operations. This allows an application which processes EDX diskette data sets to be easily modified to process exchange diskette data sets. This technique also eases the development of programs which process exchange diskettes. This is to say that the novelty of this invention lies in its improved human factors and ease of use characteristics.

Processing EDX Data Sets. In order to process an EDX data set, an application must invoke a data set open function which returns a data set control block (DSCB). The open operation sets fields in the DSCB to reflect the location and size of the data set in the diskette. In particular, the origin, length, and end of data record number of the data set have been recorded in the DSCB. Sequential processing of the data set may be performed in such a manner that the application program need not deal with the data set origin, the number of the next record to be processed, or the end of data. When the end of data is reached, the application program is so informed.

Processing Exchange Data Sets. In order to open an exchange data set, the application program must normally open the entire diskette upon which the data set resides. The program must separately maintain the origin of the data set, the next record number for subsequent input/output operations, and the end of data record number. In other words, the application program must deal with EDX and exchange data sets using very different methods. It must perform functions for itself that EDX normally provides.

Of further interest is the fact that EDX currently includes two utilities which copy data sets: - $COPYUT1, which copies EDX data sets, and

- $COPY, which copies basic exchange data sets

In essence, both programs perform the same function for different kinds of data sets.

$COPY must perform additional work to process exchange data sets for the reasons discussed previously. This is reflected in its usability characteristics; $SCOPY is difficult to use compared with $COPYUT1. Proposed Method for Processing Exchange Data Sets. The proposed method for opening an exchange data set performs operations analogous to the conventional EDX data set open...