On 1/5/2017 7:28 PM, Jesse 1 Robinson wrote:
Pretty much I would say. Just want to point out that FBS and VBS are worlds
apart. As discussed, the 'S' in VBS is 'spanned'. The 'S' in FBS means
'standard' or some such. This guarantees that the file has no short blocks
other than the very last one. A file written 'normally' is usually FBS whether
labeled that way or not, but one written to multiple times via DISP=MOD is
almost certain to have many short blocks, one for each time the file is closed
and then reopened.
I doubt that modern processing really cares, but once upon a time FBS was more
efficient than FB to read because I/O routines did not have to check for and
handle a short block on every read.
I used VBS data sets in an Assembler application that processed health
care claims under OS/MVS 21.8 back in 1978. 'S' meant spanned then and
it means spanned now.
No magic is required to read and/or write VBS or VS records, just
knowledge of what the possible values for the RDWs are.
Mike Shaw
MVS/QuickRef Support Group
Chicago-Soft, Ltd.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
