Portal | Manuals | References | Downloads | Info | Programs | JCLs | Master the Mainframes
IBM Mainframe Computers Forums Index
 
Register
 
IBM Mainframe Computers Forums Index Mainframe: Search IBM Mainframe Forum: FAQ Memberlist Usergroups Profile Log in to check your private messages Log in
 

 

Cobol Open Statement & VSAM Buffer

 
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> COBOL Programming
View previous topic :: :: View next topic  
Author Message
kevodaly

New User


Joined: 05 Mar 2009
Posts: 1
Location: Ireland

PostPosted: Thu Feb 02, 2012 1:07 am    Post subject: Cobol Open Statement & VSAM Buffer
Reply with quote

Hi.

I have a TSO batch job that acts as an interface for MQ messages. When a message is received, the program will run and depending on the transaction type, other Cobol modules may be called.

One of these modules accesses a VSAM file. This module will be called once for each message received. The module contains a Cobol OPEN, READ using a key and CLOSE of that VSAM file.

My question is, does the Cobol OPEN statement refresh buffers associated with that VSAM file? i.e. For each call of that module, will the READ of the VSAM file be a physical read, or could it fetch a record from the buffer if it happens to be in the same Control Interval.

Thanks for your help!
Kevin
Back to top
View user's profile Send private message

Bill Woodger

DFSORT Moderator


Joined: 09 Mar 2011
Posts: 7315

PostPosted: Thu Feb 02, 2012 1:27 am    Post subject: Reply to: Cobol Open Statement & VSAM Buffer
Reply with quote

I've always assumed that when you close a file, that is it. If you open again, then you'd be starting clean. No buffers until first read/write from your program.

If I wanted to hope for something different, I'd check it out in "the manuals"/google.
Back to top
View user's profile Send private message
View previous topic :: :: View next topic  
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> COBOL Programming All times are GMT + 6 Hours
Page 1 of 1

 

Search our Forum:

Similar Topics
Topic Author Forum Replies Posted
This topic is locked: you cannot edit posts or make replies. Cobol GUI (like Editor) Kala Mainframe COBOL Programming 14 Wed May 10, 2017 12:30 pm
No new posts IMS T-Pipe queue counts in a COBOL Pr... Siva NKK Kothamasu IMS DB/DC 0 Tue May 09, 2017 6:31 pm
No new posts COBOL Code Parsers and Lineage Establ... balimanja COBOL Programming 2 Tue May 02, 2017 3:30 am
No new posts Cobol upgrade - source code missing f... gthmrj IBM Tools 1 Wed Apr 26, 2017 6:04 pm
No new posts VSAM Space Allocation mrgnndhmk JCL & VSAM 7 Sat Apr 22, 2017 12:42 am


Facebook
Back to Top
 
Mainframe Wiki | Forum Rules | Bookmarks | Subscriptions | FAQ | Tutorials | Contact Us