Advanced Queuing - Oracle

AQ and Memory Usage
printf("Error - %d\n", status);
break;
}
exit(-1);
} /* end checkerr */
Dequeuing Messages (Reuse Memory) Using OCI
This program, deqreuse.c, dequeues each line of text from a queue 'msgqueue'
that has been created in scott's schema by executing create_types.sql.
Messages are enqueued using enqnoreuse.c or enqreuse.c. If there are no
messages, it waits for 60 seconds before timing out. In this program, the dequeue
subroutine reuses client side objects' memory between invocation of LNOCIAQDeq.
During the first call to LNOCIAQDeq, OCI automatically allocates the memory for
the message payload. During subsequent calls to LNOCIAQDeq, the same payload
pointers are passed and OCI will automatically resize the payload memory if
necessary.
#ifndef OCI_ORACLE
#include
#endif
#include
static void checkerr(OCIError *errhp, sword status);
static void deqmesg(text *buf, ub4 *buflen);
struct message
{
OCINumber id;
OCIString *data;
};
typedef struct message message;
struct null_message
{
OCIInd null_adt;
OCIInd null_id;
OCIInd null_data;
};
typedef struct null_message null_message;
/* Global data reused on calls to enqueue: */
LNOCIEnv *envhp;
A-84 Oracle9i Application Developer’s Guide - Advanced Queuing