Creating Utility

An access method represents the process that is used to store and retrieve data from the datasets or files.
Access Method Services (AMS) is a utility mainly used to define and handle VSAM datasets and integrated catalogs.
IDCAMS(Integrated Data Cluster Access Method Services) is the utility program name for access method services (AMS) and used to create the VSAM datasets.
The functions of AMS are performed through the different functional commands of IDCAMS.

Syntax -

//JOBNAME  JOB job-card-parameters
//STEP1    EXEC PGM=IDCAMS
//SYSPRINT DD SYSOUT=A
//SYSIN    DD *
  AMS commands and their parameters
/*

The below are AMS commands of IDCAMS -

AMS Command	Description
DEFINE	Creates catalogs and catalog entries for files, alternate indexes, paths, and VSAM data spaces.
ALTER	Alters the existing catalog entries.
LISTCAT	Lists catalog entries.
PRINT	Prints VSAM and nonVSAM files.
REPRO	Copies files.
EXPORT	Creates a copy of a file for backup or makes a file or user catalog portable to use in another system.
IMPORT	Reads a backup copy of a file or makes a file or user catalog previously exported available in another system.
VERIFY	Provoke a catalog to correctly reflect the end of a file.
DELETE	Deletes catalog entries.

Guidelines for coding commands in IDCAMS -

At least one blank space must be between the command, the object, and sub-parameter values.
Sub parameter values can be separated using a space or a comma.
Space is optional between a parameter and the parenthesis enclosing its values.
A hyphen (-) is used to specify the current line extended to the following line.

IDCAMS utility is explained in utilities section .