Processing PDSE Records

Start of change PDSE members are accessed sequentially, as are PDS members. Each member can contain a maximum number of logical records based on the rules in PDSE member size limits. A logical end-of-file mark is at the end of each PDSE member. End of change

Some restrictions on processing PDSEs follow:

The JCL keyword DSNTYPE cannot be specified with the JCL keyword RECORG.
You should not use PDSEs if your application is dependent on processing short blocks other than the last one in a member of processing or SAM record null segments. See Processing Short Blocks and Processing SAM Null Segments for more information.
See Using the BSP Macro to Backspace a Physical Record for the restrictions in using BSP with variable spanned or variable blocked spanned records.
You cannot write or update the PDSE directory using the WRITE or PUT macros. To write or update the directory, you must use the STOW or DESERV FUNC=UPDATE macros.
You cannot add or replace members of a PDSE program library using the STOW macro.
Aliases for members must point to the beginning of the member.
The deletion of the primary member name causes all aliases to be deleted.
EXCP, EXCPVR, and XDAP are not supported macros for PDSEs.
If you allocate a PDSE, it cannot be read on an earlier version or release of DFSMSdfp that does not support PDSEs.
Note lists are not supported for PDSEs. When using STOW with a PDSE, do not supply a list of TTRs in the user data field of the directory.
The CHECK, STOW, and CLOSE macros do not guarantee that the data has been synchronized to DASD. Use the SYNCDEV macro or the storage class parameter SYNCDEV=YES to guarantee synchronizing data when open for update. See Using the SYNCDEV Macro to Synchronize Data for the definition of synchronization.
DS1LSTAR field of the format 1 DSCB is unpredictable for PDSEs.
The OPTCD=W DCB parameter (write-check) is ignored for PDSEs.
A checkpoint data set cannot be a PDSE. Checkpoint fails if the checkpoint data set is a PDSE. Also, a failure occurs if a checkpoint is requested when a DCB is opened to a PDSE, or if a PDS was opened at checkpoint time but was changed to a PDSE by restart time.
Do not use the TRKCALC macro because results could be inaccurate. (However, no error indication is returned.)
When a cataloged procedure library is used, the library is opened for input and stays open for extended periods. If another user or system attempts to open the procedure library for output in a non-XCF (sysplex) environment, the second user receives an ABEND. This could prevent procedure library updates for extended periods.