Enterprise COBOL for z/OS V4.2 Programming Guide

vThe terms file in COBOL terminology and data set or HFS file in operating-systemterminology have essentially the same meaning and are used interchangeably inthis information.For Customer Information Control System (CICS) and online InformationManagement System (IMS ) message processing programs (MPP), code only theENVIRONMENT DIVISION header and, optionally, the CONFIGURATION SECTION. CICSdoes not allow COBOL definition of files. IMS allows COBOL definition of filesonly for batch programs.Provide information to control efficient transmission of the data records betweenyour program and the external medium.“Example: FILE-CONTROL entries”RELATED TASKS“Specifying the collating sequence” on page 9“Defining symbolic characters” on page 10“Defining a user-defined class” on page 10“Defining files to the operating system” on page 10RELATED REFERENCESSections and paragraphs (Enterprise COBOL Language Reference)Example: FILE-CONTROL entriesThe following table shows example FILE-CONTROL entries for a QSAM sequentialfile, a VSAM indexed file, and a line-sequential file.Table 1. FILE-CONTROL entriesQSAM file VSAM file Line-sequential fileSELECT PRINTFILE 1ASSIGN TO UPDPRINT 2ORGANIZATION IS SEQUENTIAL 3ACCESS IS SEQUENTIAL. 4 SELECT COMMUTER-FILE 1ASSIGN TO COMMUTER 2ORGANIZATION IS INDEXED 3ACCESS IS RANDOM 4SELECT PRINTFILE 1ASSIGN TO UPDPRINT 2ORGANIZATION IS LINE SEQUENTIAL 3ACCESS IS SEQUENTIAL. 4RECORD KEY IS COMMUTER-KEY 5FILE STATUS IS 5COMMUTER-FILE-STATUSCOMMUTER-VSAM-STATUS.1. The SELECT clause chooses a file in the COBOL program to be associated with an external data set.2. The ASSIGN clause associates the program’s name for the file with the external name for the actual data file. Youcan define the external name with a DD statement or an environment variable.3. The ORGANIZATION clause describes the file’s organization. For QSAM files, the ORGANIZATION clause is optional.4. The ACCESS MODE clause defines the manner in which the records are made available for processing: sequential,random, or dynamic. For QSAM and line-sequential files, the ACCESS MODE clause is optional. These files alwayshave sequential organization.5. For VSAM files, you might have additional statements in the FILE-CONTROL paragraph depending on the type ofVSAM file you use.RELATED TASKSChapter 9, “Processing QSAM files,” on page 151Chapter 10, “Processing VSAM files,” on page 179Chapter 11, “Processing line-sequential files,” on page 207“Describing the computing environment” on page 78 Enterprise COBOL for z/OS V4.2 Programming Guide