Advanced Queuing - Oracle

OCIInd null_adt;
OCIInd null_id;
OCIInd null_data;
};
typedef struct null_message null_message;
AQ and Memory Usage
static void deqmesg(buf, buflen)
text *buf;
ub4 *buflen;
{
OCIType *mesgtdo = (OCIType *)0; /* type descr of SCOTT.MESSAGE */
message *mesg = (dvoid *)0; /* instance of SCOTT.MESSAGE */
null_message *mesgind = (dvoid *)0; /* null indicator */
OCIAQDeqOptions *deqopt = (OCIAQDeqOptions *)0;
ub4 wait = 60; /* timeout after 60 seconds */
ub4 navigation = OCI_DEQ_FIRST_MSG;/* always get head of q */
/* Get the type descriptor object for the type SCOTT.MESSAGE: */
checkerr(errhp, OCITypeByName(envhp, errhp, svchp,
(CONST text *)"SCOTT", strlen("SCOTT"),
(CONST text *)"MESSAGE", strlen("MESSAGE"),
(text *)0, 0, OCI_DURATION_SESSION,
OCI_TYPEGET_ALL, &mesgtdo));
/* Allocate an instance of SCOTT.MESSAGE, and get its null indicator: */
checkerr(errhp, OCIObjectNew(envhp, errhp, svchp, OCI_TYPECODE_OBJECT,
mesgtdo, (dvoid *)0, OCI_DURATION_SESSION,
TRUE, (dvoid **)&mesg));
checkerr(errhp, OCIObjectGetInd(envhp, errhp, (dvoid *)mesg,
(dvoid **)&mesgind));
/* Allocate a descriptor for dequeue options and set wait time, navigation: */
checkerr(errhp, OCIDescriptorAlloc(envhp, (dvoid **)&deqopt,
OCI_DTYPE_AQDEQ_OPTIONS, 0, (dvoid **)0));
checkerr(errhp, OCIAttrSet(deqopt, OCI_DTYPE_AQDEQ_OPTIONS,
(dvoid *)&wait, 0, OCI_ATTR_WAIT, errhp));
checkerr(errhp, OCIAttrSet(deqopt, OCI_DTYPE_AQDEQ_OPTIONS,
(dvoid *)&navigation, 0,
OCI_ATTR_NAVIGATION, errhp));
/* Dequeue the message and commit: */
checkerr(errhp, OCIAQDeq(svchp, errhp, (CONST text *)"msgqueue",
deqopt, 0, mesgtdo, (dvoid **)&mesg,
(dvoid **)&mesgind, 0, 0));
Oracle Advanced Queuing by Example A-81