vijayaselvam
New User
Joined: 29 May 2006
Posts: 6
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The access method services program IDCAMS allows the user to determine and manage the VSAM environment. Some of the services which are performed through the IDCAMS program include:
* Defining catalogs
* Defining files,catalogs...
* Deleting files,catalogs...
* Listing files
* Converting files to VSAM
* Creating backup files
Once again, the IDCAMS program is executed through the statement:
// EXEC IDCAMS,SIZE=AUTO
Notice that the size parameter must be included to allow for space required by VSAM in the partition in which it runs.
Through IDCAMS, there are two types of commands which may be utilized. One type of command are the FUNCTIONAL commands which request some file management action to be accomplished. Some of these commands include DEFINE, DELETE, LISTCAT, PRINT,VERIFY and REPRO. The second type of command available under IDCAMS is the MODAL commands. These commands are used to specify options, delimit functional command sequences, and test condition codes. Some of these MODAL commands include IF,THEN,ELSE,DO,END,SET and PARM.
The general structure of a command under IDCAMS is
verb parameters terminator
It is vital that the proper language syntax is utilized in constructing the IDCAMS commands. This syntax is straight forward and the reader is encouraged to grasp the basic syntax requirements before attempting to utilize VSAM. The following points summarize the basic syntax of the language:
Verbs must be separated from the parameters by at least one separator
A separator is a blank or a comment
A comment is any string of characters preceded by /* and followed by */
Commands must lie between column 2 and column 72
To continue a command to the next line a hyphen must be placed before column 73 and it must be the last non-blank character on that line
A terminator indicates the end of the command
A terminator can be a semicolon or simply the absence of the continuation character (the hyphen).
If a semicolon is used as a terminator, all the characters to the right of the semicolon are ignored. |
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