examples/PIPS/opencmessagequeuelibraryex/engine/src/msgqcheck.c

#include <errno.h>
#include <sys/msg.h>
#include "MsgQInternal.h"



/*****************************************************************************
*  MsgQCheck
*  Function: Function for checking how many messages are in a queue
*******************************************************************************/

EXPORT_C int MsgQCheck(ULONG qName, int* err) {
        MSGQ_INFO* pMsgQInfo = NULL;
        int nMsgs;
        struct  msqid_ds  qStatus ;

        if ((pMsgQInfo = MsgQTableLookup(qName)) != NULL) {
                //   get total count of msgs from the msg queue 
                if ((msgctl(pMsgQInfo->qId,IPC_STAT ,&qStatus)) >= 0 ) {
                        nMsgs=qStatus.msg_qnum ;
                        if (nMsgs == pMsgQInfo->numMsgs) {
                                *err = OK;
                                return(nMsgs);
                        }
                        else {
                                *err = KMsgQLibQShortErr;
                                return(pMsgQInfo->numMsgs);
                        }
                }
                else
                        *err=errno;
        }
        else
                *err = KMsgQLibQIdErr;
        return(ERROR);
}

---