Re: Intermittent Message Subfile, works always in debug.

[Jamey Saunders <jsaund@xxxxxxxxxxxxxxxxxxxxxxxxx>]

Rory,

Yes, its RPG.

Here's the data structure definition I'm using for the Error DS:

     D*----Data structure for API error.
     D DSERR           DS
     D  @BRET                  1      4B 0 INZ(0272)
     D  @BAVL                  5      8B 0 INZ(0000)
     D  @ERRID                 9     15
     D  @DSERR                16     16
     D  @ERR                  17    272

And here's the prototype for QMHSNDPM:

     D QMHSNDPM        PR                  ExtPgm('QMHSNDPM')
     D   PR_MsgID                     7A   const
     D   PR_QualMsgF                 20A   const
     D   PR_MsgTxt                32767A   const options(*varsize)
     D   PR_MsgTxtLen                10I 0 const
     D   PR_MsgType                  10A   const
     D   PR_MsgQueues               276A   const dim(50) options(*varsize)
     D   PR_NumQueues                10I 0 const
     D   PR_MsgKey                    4A
     D   PR_ErrorCode              8000A   options(*varsize)
     D   PR_CCSID                    10I 0 const options(*nopass)

And the call to QMHSNDPM in my service program:

         CallP QMHSNDPM(INMGID:MMSGF:MDATA:MLEN:MTYPE:
                        MMSGQ:MSTACK:MKEY:DSERR);

Values when I'm in debug are:
INMGID: IRB0014 (That's the message number I'm sending from my message file)
MMSGF: 'IRBMSG    IRBPGM    '  (That's the correct qualified name of my 
message file)
MDATA: *BLANK
MLEN: 80
MTYPE: *INFO
MMSGQ: IRB201 (That's the name of the program whose message queue I want 
to write to)
MSTACK: *ZEROS
MKEY: *BLANKS
DSERR: @BRET is 272, but that's being set in the DS definition.  
Everything else in the DSERR structure is zeros or blank.

Does that help?

Best Regards,
Jamey Saunders

On 2/6/2012 3:29 PM, Rory Hewitt wrote:
> Jamey,
>
> In my experience, there are 2 reasons why something works in debug and
> doesn't work otherwise:
>
> 1. Timing. Running a program in debug takes longer - mainly because you're
> stopping it every so often to check field values. In programs that make use
> of things like semaphores, mutexes, shared memory and where there are other
> programs accessing the same data or sending receiving signals, data queue
> entries etc from your program, this can change things drastically.
>
> 2. Memory initialization. When a program is loaded , it allocates whatever
> memory it needs from the OS to do its thing. If you run it in debug, the
> memory may be allocated differently than when not in debug. I think the
> debugger may pre-initialize the memory heap in some way, but I'm not sure.
>
> You're almost certainly a victim of #2. Check your numeric variables,
> specifically those that are subfields in a data-structure? Do you
> explicitly initialize them? If not, then in debug, the memory over which
> they are overlaid may be set to hex zeroes anyway, so they implicitly
> initialize to 0, but when not in debug, it may be some other value.
>
> Do you check/set QUSEC prior to calling QMHSNDPM? If so, do you check it
> afterwards?
>
> If necessary, add a DUMP statement to your program (and or multiple
> DSPLY's) - I'm assuming this is RPG - although that may cause a different
> memory layout anyway.
>
> HTH,
>
> Rory
>
> On Mon, Feb 6, 2012 at 11:46 AM, Jamey Saunders<
> jsaund@xxxxxxxxxxxxxxxxxxxxxxxxx>  wrote:
>
> > Hi Everyone,
> >
> > Here's something that has had me stumped for two days.  I have a display
> > file with a message subfile.  I am sending the messages using QMHSNDPM
> > wrapped in a service program.  I have a block of code that does some
> > sanity checks on the subfile control data and sends messages to the
> > program queue for display as appropriate.  I am also clearing the
> > message queue whenever the subfile is acted on and control is returned
> > to the program (i.e.: someone does something and presses Enter).
> >
> > My issue is this:  Some of my messages display properly.  Some of my
> > messages do not display at all.  It is always the same messages that
> > display, and always the same messages that do not.  Here's the kicker,
> > though:  If I put my program into debug, and step past the call to the
> > ShowMsg procedure in my service program, then hit F12, every single
> > message displays properly.
> >
> > None of my colleagues can figure this one out, though one of them says
> > that he's seen this happen before where something worked in debug that
> > didn't work otherwise, and he thinks it was subfile-related.  He doesn't
> > remember what the fix was, though.
> >
> > Anybody ever run into something like this?  I'll post any code that
> > anyone deems relevant, even though the messaging is working properly
> > some of the time.
> >
> > Best Regards,
> > Jamey Saunders
> > --
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