On Tue, 23 Jan 2007 12:50:09 -0500, Bruce Black wrote: > > > publibz. And note that the mechanism is not described. It could > > be by writing an EOF at the beginning; it could be that a flag is > > set (in the DSCB?) to indicate that the data set is uninitialized. > > > It is done by writing an EOF on the first track at the time the dataset > I wonder why the omitted the central implementation detail, and why they did not include EXCP as a supported access technique.
> is allocated. There is no option to control this. Most JCL allocates > sequential datasets without specifying DSORG (the DSORG is not > determined until the dataset is opened for output), so IBM decided to do > this for all SMS datasets with DSORG=PS or null. > I thought someone once informed me that the reason I didn't get an EOF in a particular instance was that SMS couldn't determine the DSORG. I'm tempted to try again. > They could have easily done this for non-SMS as well, but I guess they > opted for "compatibility". > Compatibility with what? Is there some application that depends on uninitialized space not starting with an EOF? That can't generally be guaranteed. But I'd suggest the EOF not be written when ABSTRK is specified -- someone might be trying to recover deleted data. That said, I try not to urge that such solutions be retrofitted to obsolescent environments such as non-SMS. Rather, the users should be encouraged to migrate forward to (e.g.) SMS. -- gil -- StorageTek INFORMATION made POWERFUL ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
