Re: rcvmsg question

On 05-Nov-2014 13:20 -0600, rob@xxxxxxxxx wrote:

<<SNIP>>
dountil [...]
RCVMSG MSGQ(&MsgQLib/&MsgQName) WAIT(10) +
MSGID(&MSGID) RMV(*NO)
<<SNIP>>

That Receive Message (RCVMSG) request is presumed to default to MSGTYPE(*ANY) and MSGKEY(*NONE)

and the message CPF1817 goes to the message queue after the timeout
on the RCVMSG line but before it loops back to RCVMSG does the RCVMSG
catch that message or only new messages?

The Receive Message (RCVMSG) is effectively an overloading, effecting the operation of either of the Receive Program Message (QMHRCVPM) API or the Receive Nonprogram Message (QMHRCVM) API. Per the specification of the Message Queue (MSGQ) parameter naming an object [vs redirect to the PGMQ() parameter], the usage is the latter API. Referring to the doc for that API, the following quoted text is applicable [when lookup on the term /optional/ for the description of the combination of chosen specifications for both "Message Types and Message Keys" parameters:

<http://www.ibm.com/support/knowledgecenter/api/content/nl/en-us/ssw_ibm_i_71/apis/Qmhrcvm.htm>
_Receive Nonprogram Message (QMHRCVM) API_
"...
When you do not specify a message key, the first _new message_ of the specified type is received. If a new message of that type is not in the message queue, no error is returned. ...
..."

I guess a test would be send some messages to a message queue. Start
a test program that does a RCVMSG against that queue. Does the test
return the missed message(s) or does it only wait on new messages?

Also in the above doc link: "*New messages* are messages that have been sent to a queue and have not yet been received."

That test should confirm that a message that was sent between the prior RcvMsg request and the current RcvMsg request, should be the _new_ message received by the current RcvMsg request. The RcvMsg request will not /wait/ only for a\some even _newer_ message.