IBM Mainframe Forum

Hi

I have a long-running application that closes and then reopens a dataset, which is fine. The problem occurs when a user decides to code FREE=CLOSE on the DD statement in the JOB's JCL.

Needless to say, when the application tried to reopen the dataset, the FREE=CLOSE function had removed the DDNAME from the TIOT and all related control blocks from the system.

There appears to be a bit in the DSAB and SIOT related to FREE=CLOSE. Is there a supported way to turn those bits off prior to issuing the close for the dataset?

A ZOS macro IEFDDSRV that implies that it can modify allocation information, but it is not very well documented as to what is required for the MODIFY=ALLOCATION request.

Does anyone have any experience with the IEFDDSRV function or know of other supported ways to prevent ZOS from performing the FREE=CLOSE when a dataset is closed?

Thanks in advance for any assistance that is offered.

JD

jdechirico wrote:The problem occurs when a user decides to code FREE=CLOSE on the DD statement in the JOB's JCL.

I believe if the user decided to code ANY parameters, either in DD statement, or in another program code, he must be aware of the consequences of his changes.

In such manner, a user can change hundreds, or thousands of different options, flags, or values. It is not possible for administration to programmatically fix hundreds of possible user's "decisions" except strict requirements to the user not to use unneeded, or harmful parameters, options, or flags in his coding.