On Sun, 12 Nov 2023 17:14:49 -0700, Paul Gilmartin wrote:
>RECFM=FBS prevents that.
That is certainly a partial solution but the correct solution is VSAM RRDS or
ESDS which eliminates the special handling.
>That's mostly how the Divide instruction works.
Division is not the hard part. Impleme
On 11/12/23 16:18:04, Jon Perryman wrote:
Specifically asked was z/OS RECFM=FB. As long no one ever uses DISP=MOD, then
the calculation is simple because number of records per block and blocks per
track is consistent.
RECFM=FBS prevents that.
You simply divide record number by records per
Everyone is making this far more complicated than it needs to be. Positioning a
file is about you designing a method that can calculate a position on the disk
that meets your requirements. z/OS, Unix, CMS, z/VSE and MS-Windows have file /
dataset positioning because it greatly reduces I/O. There
On 11/11/23 19:36:36, Seymour J Metz wrote:
It is possible to do skip sequential reading of physical records. Itt is not
possible to skip logical records.
There are two cases where it is possible; RECFM=FBS and you know the physical
record number; you know the TTR of the physical record.
w
