Gerhard, Does this ALLDATA change the access method used by DFSMSdss? For logical copy I've found that DFSMSdss actually calls utilities like IDCAMS and IEBCOPY to read or write the dataset. I'm guessing that using ALLDATA to read all the allocated space for a dataset would cause DFSMSdss invoke an access method that is not concerned when the physical structure of the file changes part way through.
Ron > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf Of Gerhard Postpischil > Sent: Sunday, March 18, 2012 7:02 AM > To: [email protected] > Subject: Re: [IBM-MAIN] IEFBR14 > > On 3/18/2012 9:03 AM, Ron Hawkins wrote: > > And finally, my memory may be a bit dodgy nowadays, but it's my > > recollection that the EOF for empty datasets was introduced so that > > DFSMShsm and DFSMSdss could migrate, move and copy empty datasets. > > When there is no EOF for a zero empty dataset these utilities choke > > and spit it back. I don't think security was an objective. > > When you use the ALLDATA option, DSS copies whatever exists past the last > valid EOF. This means that it has the capability of copying anything, regardless > of DCB parameters, or whether or not those tracks have been used. So > exactly what condition would "choke and spit it back"? > > I guess that DSS, and presumably HSM, use a Read Track or Read Track > Multiple, and the only condition that might cause a problem would be an > uninitialized track, lacking basic home address information. > > Gerhard Postpischil > Bradford, VT > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, send email to > [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
