Re: Problem receiving a message using qmhrcvpm

[Robert Rogerson <rogersonra@xxxxxxxxx>]

Thanks Scott for the explanation.  This leads me to an approach based on
Scott's information.  I'm wondering if it possible to update/change an entry
already written to the queue.

What I'm thinking is to write a marker in ProgA before calling ProgB as
Scott suggested.
Change ProgC to pass 'ProgA' to ProgD to write the message. (Currently it is
passing 'ProgC')

After ProgB returns ProgA's queue would hold (on an error)
ProgAMarker
Error Details

Could I now change the 'ProgAMarker' to 'Failure'?  So the queue now holds
Failure
Error Details
And I could then display the queue as is.

If I can't update/change then I would have to
Dou message = Failure
If message = Failure
Get next message and save it
Endif
Get next message
Enddo
Write Failure message
Write saved message

I guess what I'm really asking is can I update a message that has already
been written to a program queue or to change it it must be deleted and then
written?

Thanks,

Rob

On Tue, Apr 20, 2010 at 2:10 PM, Scott Klement <rpg400-l@xxxxxxxxxxxxxxxx>wrote:

> Robert,
>
> Once a call stack has ended (as is the case with 'ProgD' in your
> example) you can no longer refer to messages in it's message queue by
> the call stack level or program name.
>
> However, you can still work with the message by message key.
>
> You appear to be saving the key to &W@MSGNO, so you could potentially
> pass that back up the call stack.
>
> If you don't have the message key for the message, then there are two
> ways to get it.  (1) You can call the QMHLJOBL API which lists the whole
> job log (including message keys for all messages) to a user space. (2)
> or, you can rely on the fact that message keys are really a 4-byte
> integer value, the OS keeps adding to it for every new message.  So you
> could loop through a range of numbers and look for your message.
> (Usually you do this by putting a "marker" mesage in the jog before
> calling ProgB, and then another "marker" message after ProgB ends...
> that gives you from/to keys that you can loop between.)
>
> Hope that helps.
>
> On 4/20/2010 9:57 AM, Robert Rogerson wrote:
> > I'm having trouble receiving a message which I can see in the job log.
>  Here
> > is the scenario...
> >
> > ProgA calls ProgB
> > ProgB calls ProgC
> > An error occurs in ProgC
> > ProgC calls ProgD to send the message
> > ProgD sends the message (SNDPGMMSG MSGID(WDC0145) MSGF(TFMMSG) MSGDTA('
> ')
> > TOPGMQ(*SAME
> > ('WIM331')) KEYVAR(&W@MSGNO)
> > ProgD ends
> > ProgC ends
> > ProgB ends returning an error
> > If an error occurred
> > // Receive program message
> > QMHRCVPM( msgBack
> > : %Size(msgBack)
> > : 'RCVM0100'
> > : '*'
> > : 0
> > : '*PRV'
> > : Pm_MKey
> > : 0
> > : '*SAME'
> > : Qusec )
> >
> > I want to receive the message issued by ProgD (this may be different
> errors
> > depending on the error generated in ProgC) so I may display it in ProgA
> to
> > give a better indication of what error occurred.
> > One condition I should add is that ProgC and ProgD are vendor supplied
> > programs I am trying to avoid changing.
> >
> > Can anyone shed some light on what I am doing wrong?
> >
> > Thanks,
> >
> > Rob
>
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