On 10/9/2012 6:36 PM, Paul Gilmartin wrote:
I suppose that when doing a gather-write, FORTRAN (which seems to be a primary motivator for VBS) knows where the segments are coming from and can build SDWs; no such rationale applies to a scatter-read.
Last time I looked at ForTran library code, it used BSAM for all I/O, in order to accommodate backspace, open in/out and out/in, etc. So none of the QSAM limitations should apply (I seem to recall a fix against the G level library for four byte RDWs in the sixties).
I think that's pretty much subsumed by the statement that the minimum count allowed is 5. But it's a pity they didn't do it reasonably so that a VBS data stream would be a compatible superset of a VB data stream.
My recommendation for a documentation change is based on the fact that users of BSAM have the ability to write meaningful code using short records; just the ability to write a variable number of null intermediate segments offers itself for nefarious uses not readily detectable without source or data inspection.
Gerhard Postpischil Bradford, VT ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
