SImple READ DI - no key.

I would think that you would have to give a starting block address for a
direct read. But it has been many years since I wrote BDAM code.

On Thu, 19 Jul 2012 11:00:08 -0400 Thomas David Rivers <[email protected]>
wrote:

:>Thomas David Rivers wrote:
:>
:>> I'm debugging a program (no source), and trying to
:>> figure out what BDAM does when the READ macro
:>> is invoked without a BLKREF relative-block-address
:>> specified.
:>>
:>> This is an RBA-type BDAM, and I'm seeing a READ
:>> where the BLKREF in the DECB is simply X'0'.
:>>
:>
:>Binyamin Dissen asked:
:>
:>
:>
:>   What is the second parameter of the read?
:>
:>   --
:>   Binyamin Dissen <[email protected]>
:>   http://www.dissensoftware.com
:>
:>
:>The parms passed to the READ SVC (addressed by R1) are
:>
:> 0    X'00000000'
:> 4    X'0048' 
:> 6    X'0000'  (zero length, use the blksize from the DCB?)
:> 8    X'0000BFF8'     (address of the DCB)
:> 12  X'00016000'      (AREA ADDRESS)
:> 16  X'00000000'      (IOB ADDRESS)
:> 20  X'00000000'      (KEY ADDRESS)
:> 24  X'0000c40c'      (BLKREF ADDRESS)
:>
:>
:>It seems I had mis-counted, and its the KEY ADDRESS that
:>is X'0' - not the BLKREF ADDRESS (which is actually not X'0')
:>(I'm laying out my error for the proper group humiliation :-) :-) :-) )
:>
:>But, since I don't seem to be able to count... is that
:>the proper layout of the parms to the READ SVC?
:>
:>And - back to the original question, is there _ever_ a situation
:>in a BDAM READ where the BLKREF address _could_ be X'0'?
:>(Today, I'm guessing not...)
:>
:>    - Thanks! -
:>    - Dave Rivers -

--
Binyamin Dissen <[email protected]>
http://www.dissensoftware.com

Director, Dissen Software, Bar & Grill - Israel


Should you use the mailblocks package and expect a response from me,
you should preauthorize the dissensoftware.com domain.

I very rarely bother responding to challenge/response systems,
especially those from irresponsible companies.

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

Reply via email to