+

Search Tips | Advanced Search

MQINQ - Inquire object attributes

The MQINQ call returns an array of integers and a set of character strings containing the attributes of an object.

The following types of object are valid:


Syntax

MQINQ (Hconn, Hobj, SelectorCount, Selectors, IntAttrCount, IntAttrs, CharAttrLength, CharAttrs, CompCode, Reason)


Parameters


Usage notes

  1. The values returned are a snapshot of the selected attributes. There is no guarantee that the attributes remain the same before the application can act upon the returned values.
  2. When you open a model queue, a dynamic local queue is created. A dynamic local queue is created even if you open the model queue to inquire about its attributes. The attributes of the dynamic queue are largely the same as the attributes of the model queue at the time that the dynamic queue is created. If you then use the MQINQ call on this queue, the queue manager returns the attributes of the dynamic queue, and not the attributes of the model queue. See Table 1 for details of which attributes of the model queue are inherited by the dynamic queue.
  3. If the object being inquired is an alias queue, the attribute values returned by the MQINQ call are the attributes of the alias queue. The are not the attributes of the base queue or topic to which the alias resolves.
  4. If the object being inquired is a cluster queue, the attributes that can be inquired depend on how the queue is opened:

    • We can open a cluster queue for inquire plus one or more of the input, browse, or set operations. To do so, there must be a local instance of the cluster queue for the open to succeed. In this case, the attributes that can be inquired are the attributes that are valid for local queues.
    • If the cluster queue is opened for inquire alone, or inquire and output, only the attributes listed can be inquired. The QType attribute has the value MQQT_CLUSTER in this case:

      • MQCA_Q_DESC
      • MQCA_Q_NAME
      • MQIA_DEF_BIND
      • MQIA_DEF_PERSISTENCE
      • MQIA_DEF_PRIORITY
      • MQIA_INHIBIT_PUT
      • MQIA_Q_TYPE

      We can open the cluster queue with no fixed binding. We can open it with MQOO_BIND_NOT_FIXED specified on the MQOPEN call. Alternatively, specify MQOO_BIND_AS_Q_DEF, and set the DefBind attribute of the queue to MQBND_BIND_NOT_FIXED. If you open a cluster queue with no fixed binding, successive MQINQ calls for the queue might inquire different instances of the cluster queue. However, it is typical for all the instances have the same attribute values.

    • An alias queue object can be defined for a cluster. Because TARGTYPE and TARGET are not cluster attributes, the process performing an MQOPEN process on the alias queue is not aware of the object to which the alias resolves.

      During the initial MQOPEN, the alias queue resolves to a queue manager and a queue in the cluster. Name resolution takes place again at the remote queue manager and it is here that the TARGTPYE of the alias queue is resolved.

      If the alias queue resolves to a topic alias, then publication of messages put to the alias queue takes place at this remote queue manager.

    See Cluster queues
  5. You might want to inquire a number of attributes, and then set some of them using the MQSET call. To program inquire and set efficiently, position the attributes to be set at the beginning of the selector arrays. If we do so, the same arrays with reduced counts can be used for MQSET.
  6. If more than one of the warning situations arise (see the CompCode parameter), the reason code returned is the first one in the following list that applies:
    1. MQRC_SELECTOR_NOT_FOR_TYPE
    2. MQRC_INT_ATTR_COUNT_TOO_SMALL
    3. MQRC_CHAR_ATTRS_TOO_SHORT
  7. The following topic have information about object attributes:


C invocation

MQINQ (Hconn, Hobj, SelectorCount, Selectors, IntAttrCount, IntAttrs,
      CharAttrLength, CharAttrs, &CompCode, &Reason);
Declare the parameters as follows: 
MQHCONN  Hconn;           /* Connection handle */
MQHOBJ   Hobj;            /* Object handle */
MQLONG   SelectorCount;   /* Count of selectors */
MQLONG   Selectors[n];    /* Array of attribute selectors */
MQLONG   IntAttrCount;    /* Count of integer attributes */
MQLONG   IntAttrs[n];     /* Array of integer attributes */
MQLONG   CharAttrLength;  /* Length of character attributes buffer */
MQCHAR   CharAttrs[n];    /* Character attributes */
MQLONG   CompCode;        /* Completion code */
MQLONG   Reason;          /* Reason code qualifying CompCode */


COBOL invocation

     CALL 'MQINQ' USING HCONN, HOBJ, SELECTORCOUNT, SELECTORS-TABLE,
                        INTATTRCOUNT, INTATTRS-TABLE, CHARATTRLENGTH,
                        CHARATTRS, COMPCODE, REASON.
Declare the parameters as follows: 
**   Connection handle
 01  HCONN            PIC S9(9) BINARY.
**   Object handle
 01  HOBJ             PIC S9(9) BINARY.
**   Count of selectors
 01  SELECTORCOUNT    PIC S9(9) BINARY.
**   Array of attribute selectors
 01  SELECTORS-TABLE.
  02  SELECTORS        PIC S9(9) BINARY OCCURS n TIMES.
**   Count of integer attributes
 01  INTATTRCOUNT     PIC S9(9) BINARY.
**   Array of integer attributes
 01  INTATTRS-TABLE.
  02  INTATTRS         PIC S9(9) BINARY OCCURS n TIMES.
**   Length of character attributes buffer
 01  CHARATTRLENGTH   PIC S9(9) BINARY.
**   Character attributes
 01  CHARATTRS        PIC X(n).
**   Completion code
 01  COMPCODE         PIC S9(9) BINARY.
**   Reason code qualifying COMPCODE
 01  REASON           PIC S9(9) BINARY.


PL/I invocation

call MQINQ (Hconn, Hobj, SelectorCount, Selectors, IntAttrCount,
           IntAttrs, CharAttrLength, CharAttrs, CompCode, Reason);
Declare the parameters as follows: 
dcl Hconn           fixed bin(31);  /* Connection handle */
dcl Hobj            fixed bin(31);  /* Object handle */
dcl SelectorCount   fixed bin(31);  /* Count of selectors */
dcl Selectors(n)    fixed bin(31);  /* Array of attribute selectors */
dcl IntAttrCount    fixed bin(31);  /* Count of integer attributes */
dcl IntAttrs(n)     fixed bin(31);  /* Array of integer attributes */
dcl CharAttrLength  fixed bin(31);  /* Length of character attributes
                                       buffer */
dcl CharAttrs       char(n);        /* Character attributes */
dcl CompCode        fixed bin(31);  /* Completion code */
dcl Reason          fixed bin(31);  /* Reason code qualifying
                                       CompCode */


High Level Assembler invocation

         CALL MQINQ,(HCONN,HOBJ,SELECTORCOUNT,SELECTORS,INTATTRCOUNT,  X
               INTATTRS,CHARATTRLENGTH,CHARATTRS,COMPCODE,REASON)
Declare the parameters as follows: 
HCONN           DS  F      Connection handle
HOBJ            DS  F      Object handle
SELECTORCOUNT   DS  F      Count of selectors
SELECTORS       DS  (n)F   Array of attribute selectors
INTATTRCOUNT    DS  F      Count of integer attributes
INTATTRS        DS  (n)F   Array of integer attributes
CHARATTRLENGTH  DS  F      Length of character attributes buffer
CHARATTRS       DS  CL(n)  Character attributes
COMPCODE        DS  F      Completion code
REASON          DS  F      Reason code qualifying COMPCODE


Visual Basic invocation

MQINQ Hconn, Hobj, SelectorCount, Selectors, IntAttrCount, IntAttrs,
      CharAttrLength, CharAttrs, CompCode, Reason
Declare the parameters as follows: 
Dim Hconn          As Long   'Connection handle'
Dim Hobj           As Long   'Object handle'
Dim SelectorCount  As Long   'Count of selectors'
Dim Selectors      As Long   'Array of attribute selectors'
Dim IntAttrCount   As Long   'Count of integer attributes'
Dim IntAttrs       As Long   'Array of integer attributes'
Dim CharAttrLength As Long   'Length of character attributes buffer'
Dim CharAttrs      As String 'Character attributes'
Dim CompCode       As Long   'Completion code'
Dim Reason         As Long   'Reason code qualifying CompCode'