data types, detailed description, structures" /> Event message MQMD (message descriptor)

 

Event message MQMD (message descriptor)

The MQMD structure describes the information that accompanies the message data of an event message. For a full description of MQMD, including a description of the elementary datatype of each parameter, see the WebSphere MQ Application Programming Reference manual.

For an event message, the MQMD structure contains these values:

StrucId

Description: Structure identifier.
Datatype: MQCHAR4.
Value: MQMD_STRUC_ID

Version

Description: Structure version number.
Datatype: MQLONG.
Values:

MQMD_VERSION_1

Version-1 message descriptor structure, supported in all environments.

MQMD_VERSION_2

Version-2 message descriptor structure, supported on AIX, HP-UX, z/OS, Compaq NonStop Kernel, HP OpenVMS, i5/OS, Solaris, Linux, Windows, and all WebSphere MQ clients connected to these systems.

Report

Description: Options for report messages.
Datatype: MQLONG.
Value:

MQRO_NONE

No reports required.

MsgType

Description: Indicates type of message.
Datatype: MQLONG.
Value: MQMT_DATAGRAM.

Expiry

Description: Message lifetime.
Datatype: MQLONG.
Value:

MQEI_UNLIMITED

The message does not have an expiry time.

Feedback

Description: Feedback or reason code.
Datatype: MQLONG.
Value: MQFB_NONE.

Encoding

Description: Numeric encoding of message data.
Datatype: MQLONG.
Value: MQENC_NATIVE.

CodedCharSetId

Description: Character set identifier of event message data.
Datatype: MQLONG.
Value: Coded character set ID (CCSID) of the queue manager generating the event.

Format

Description: Format name of message data.
Datatype: MQCHAR8.
Value:

MQFMT_EVENT

Event message.

Priority

Description: Message priority.
Datatype: MQLONG.
Value:

MQPRI_PRIORITY_AS_Q_DEF

The priority is that of the event queue.

Persistence

Description: Message persistence.
Datatype: MQLONG.
Value:

MQPER_PERSISTENCE_AS_Q_DEF

The priority is that of the event queue.

MsgId

Description: Message identifier.
Datatype: MQBYTE24.
Value: A unique value generated by the queue manager.

CorrelId

Description: Correlation identifier.
Datatype: MQBYTE24.
Value:

For performance, queue manager, logger, channel, bridge, and SSL events:

MQCI_NONE

No correlation identifier is specified. This is for private queues only.

For such events on a shared queue, a nonzero correlation identifier is set. This parameter is set so that we can track multiple event messages from different queue managers. The characters are specified below:

1-4 Product identifier ('CSQ ')

5-8 Queue-sharing group name

9 Queue manager identifier

10-17 Time stamp

18-24 Nulls

For configuration and command events:

A unique nonzero correlation identifier

All messages relating to the same event have the same CorrelId.

BackoutCount

Description: Backout counter.
Datatype: MQLONG.
Value: 0.

ReplyToQ

Description: Name of reply queue.
Datatype: MQCHAR48.
Values: Blank.

ReplyToQMgr

Description: Name of reply queue manager.
Datatype: MQCHAR48.
Value: The queue manager name at the originating system.

UserIdentifier

Description: Identifies the application that originated the message.
Datatype: MQCHAR12.
Value: Blank.

AccountingToken

Description: Accounting token that allows an application to charge for work done as a result of the message.
Datatype: MQBYTE32.
Value: MQACT_NONE.

ApplIdentityData

Description: Application data relating to identity.
Datatype: MQCHAR32.
Values: Blank.

PutApplType

Description: Type of application that put the message.
Datatype: MQLONG.
Value:

MQAT_QMGR

Queue manager generated message.

PutApplName

Description: Name of application that put the message.
Datatype: MQCHAR28.
Value: The queue manager name at the originating system.

PutDate

Description: Date when message was put.
Datatype: MQCHAR8.
Value: As generated by the queue manager.

PutTime

Description: Time when message was put.
Datatype: MQCHAR8.
Value: As generated by the queue manager.

ApplOriginData

Description: Application data relating to origin.
Datatype: MQCHAR4.
Value: Blank.

Note:
If Vis MQMD_VERSION_2, the following additional fields are present:

GroupId

Description: Identifies to which message group or logical message the physical message belongs.
Datatype: MQBYTE24.
Value:

MQGI_NONE

No group identifier specified.

MsgSeqNumber

Description: Sequence number of logical message within group.
Datatype: MQLONG.
Value: 1.

Offset

Description: Offset of data in physical message from start of logical message.
Datatype: MQLONG.
Value: 0.

MsgFlags

Description: Message flags that specify attributes of the message or control its processing.
Datatype: MQLONG.
Value: MQMF_NONE.

OriginalLength

Description: Length of original message.
Datatype: MQLONG.
Value: MQOL_UNDEFINED.