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

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


/****************************************************************************
* MsgQClean (qName, err)
* Description: Function that empties the specified queue
*****************************************************************************/

EXPORT_C int MsgQClean(ULONG qName, int* err) {
        MSGQ_INFO* pMsgQInfo = NULL;
        char msg[MAX_MSG_LEN];
        int rcv_err;

        if ((pMsgQInfo = MsgQTableLookup(qName)) != NULL) {
                // sending a message is not allowed
                pMsgQInfo->sendState = MSG_Q_CLEANING;
                // empty out the queue 
                while(MsgQReceive(qName, msg, MAX_MSG_LEN, IPC_NOWAIT, &rcv_err) != ERROR) {};
                if (rcv_err == ENOMSG) {
                        *err = OK;
                        return (OK);
                }
                else
                        *err = rcv_err;
                // sending a message is allowed
                pMsgQInfo->sendState = MSG_Q_READY;
        }
        else
                *err = KMsgQLibQIdErr;

        return(ERROR);
}

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