From Jim Mulder:


Jim Mulder
2/4/17
to 
There are no coding requirements for the application, When you do 
a QSAM OPEN for Input, the first read-ahead I/Os are scheduled by OPEN, 
and the application program can proceed without waiting after the OPEN at 

least to the point of doing the first GET. Subsequent read-ahead I/Os can 

overlap with the application program processing. 
Sent from my iPhone

> On Mar 21, 2021, at 10:21 AM, Joseph Reichman <[email protected]> wrote:
> 
> I don’t understand what the statement “QSAM does overlapped I/O automatically”
> 
> When I do a qsam get the physical I/O is for 1 block every get just ups a 
> pointer 
> 
> BSAM allows me to do multiple Reads each with their own DECB
> 
> So I already initiate lots of physical I/O mainly because I have lots of 
> records or blocks 
> 
> I find it hard to believe that a qsam get does anything more than read 1 
> block 
> 
> Thanks 
> 
>> On Mar 20, 2021, at 2:49 PM, Binyamin Dissen <[email protected]> 
>> wrote:
>> 
>> On Fri, 19 Mar 2021 14:09:59 -0400 Joseph Reichman <[email protected]>
>> wrote:
>> 
>> :>When doing overlapped I/O is there a way to tell if the I/O had completed 
>> on the subsequent reads 
>> 
>> :>I check to see if the first fullword has been populated by the BDW
>> 
>> Did you try without overlapping I/O?
>> 
>> Post the code.
>> 
>> --
>> Binyamin Dissen <[email protected]>
>> http://www.dissensoftware.com
>> 
>> Director, Dissen Software, Bar & Grill - Israel
>> 
>> ----------------------------------------------------------------------
>> For IBM-MAIN subscribe / signoff / archive access instructions,
>> send email to [email protected] with the message: INFO IBM-MAIN
> 
> ----------------------------------------------------------------------
> For IBM-MAIN subscribe / signoff / archive access instructions,
> send email to [email protected] with the message: INFO IBM-MAIN

--------------------------------------------------------------------------------
This e-mail message, including any attachments, appended messages and the
information contained therein, is for the sole use of the intended
recipient(s). If you are not an intended recipient or have otherwise
received this email message in error, any use, dissemination, distribution,
review, storage or copying of this e-mail message and the information
contained therein is strictly prohibited. If you are not an intended
recipient, please contact the sender by reply e-mail and destroy all copies
of this email message and do not otherwise utilize or retain this email
message or any or all of the information contained therein. Although this
email message and any attachments or appended messages are believed to be
free of any virus or other defect that might affect any computer system into
which it is received and opened, it is the responsibility of the recipient
to ensure that it is virus free and no responsibility is accepted by the
sender for any loss or damage arising in any way from its opening or use.


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

Reply via email to