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
 

 

If we specify block contains zero what happens

 
Post new topic   Reply to topic    IBMMAINFRAMES.com Support Forums -> JCL & VSAM
View previous topic :: :: View next topic  
Author Message
chenchi

New User


Joined: 10 Jun 2004
Posts: 12
Location: Bangalore,India

PostPosted: Fri Jun 18, 2004 3:51 pm    Post subject: If we specify block contains zero what happens
Reply with quote

hi
1.if we don't specify 'block contains ' clause in fd section...what will happen
2.if we specify block contains zero what happens..

plz answer
Back to top
View user's profile Send private message

rick

New User


Joined: 18 Jun 2004
Posts: 59
Location: Chennai

PostPosted: Fri Jun 18, 2004 4:36 pm    Post subject:
Reply with quote

Hi,


If u specify Block contains 0 in COBOL pgm the JCL decides the block size with the BLOCKSIZE parameter.
Back to top
View user's profile Send private message
sats456

New User


Joined: 29 May 2005
Posts: 12

PostPosted: Sun Jun 05, 2005 12:30 am    Post subject: Re: If we specify block contains zero what happens
Reply with quote

Do you mean to say if we specify BLOCK CONTAINS 0 RECORDS in a COBOL program,the value specified in BLKSIZE part of DCB parameter from JCL will be picked up ??
If that is the case what is the point in specifying in COBOL pgm ?
Back to top
View user's profile Send private message
priya

Moderator


Joined: 24 Jul 2003
Posts: 568
Location: Bangalore

PostPosted: Sun Jun 05, 2005 12:38 am    Post subject:
Reply with quote

Quote:
If that is the case what is the point in specifying in COBOL pgm ?


Just for a reference. But it's not must.
Back to top
View user's profile Send private message
Aditya Bhardwaj
Warnings : 1

New User


Joined: 02 Nov 2004
Posts: 18
Location: Noida, India

PostPosted: Mon Jun 06, 2005 1:51 pm    Post subject:
Reply with quote

Hi Chenchi,

If we say BLOCK CONATAINS 0 RECORDS, then in that case, the most optimum BLOCK SIZE for that particular LRECL is decided by MVS and that particular BLOCKSIZE is allocated. IF you want to check it, just run a program with BLKSIZE SIZE 0 and then see the properties of the output file created, it will automatically have a BLKSIZE allocated.

And one more thing, there is a tool called BLKSIZE calculator, which is available, just give your LRECL and expected number of records in that file and it will provide U with the optimum number of BLKSIZE to be specifieed for that file.
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 -> JCL & VSAM All times are GMT + 6 Hours
Page 1 of 1

 

Search our Forum:

Similar Topics
Topic Author Forum Replies Posted
No new posts SORT Block of records girishb2 DFSORT/ICETOOL 12 Thu Sep 15, 2016 8:58 am
No new posts Which Control block has the DSNTYPE i... sudarshan.srivathsav PL/I & Assembler 4 Thu Jan 28, 2016 11:29 pm
No new posts NDM a variable block file spoorni IBM Tools 5 Wed Dec 23, 2015 6:08 am
No new posts VSAM file shows zero record length wi... sudhakar_mainframe JCL & VSAM 14 Sat Sep 28, 2013 9:03 am
No new posts Copy from Variable block file to anot... shanudarling JCL & VSAM 1 Fri Jul 12, 2013 5:04 am


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