>From page 15 of "OS/VS VSAM Data Set Sharing" GG22-9043:-

 

Cross-region or Cross-System SHAREOPTION 4 - .....VSAM takes three other
special actions as the data set is being processed:

 

*       A change of High Used RBA is prevented.  For a KSDS, this means no
CA splits, no adds of  new Cas to the end of the dataset, and consequently
no new extents.  For an ESDS or an RRDS, it means no Cis can be added to the
end of the dataset.
*       A change of High-key RBA is prevented (KSDS only).  This means that
the high-key CI cannot be split and that new Cis cannot be added logically
to the end of the data set.  However, free space imbedded within the file
can be used.
*       Data and sequence set buffers are refreshed for direct processing.
(more stuff that does not relate to the problem you describe).

 

The manual was written in 1980!  I am not aware of any changes since then,
but it is an area of VSAM with which I did not have much involvement - most
users avoided SHR(,4) like the plague!

 

Mike Kerford-Byrnes

 


----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: INFO IBM-MAIN

Reply via email to