handling "zero" mergeToGroup value

@tinmyo.win

I assume that you are connecting to TREP. TREP manages the groupID and it will send mergeToGroup with zero value after the service is down.

<updateMsg domainType="RSSL_DMT_SOURCE" streamId="2" containerType="RSSL_DT_MAP" flags="0xC0 (RSSL_UPMF_DO_NOT_CACHE|RSSL_UPMF_DO_NOT_CONFLATE)" updateType="0 (RDM_UPD_EVENT_TYPE_UNSPECIFIED)" dataSize="51">
    <dataBody>
        <map flags="0x0" countHint="0" keyPrimitiveType="RSSL_DT_UINT" containerType="RSSL_DT_FILTER_LIST" >
            <mapEntry flags="0x0" action="RSSL_MPEA_UPDATE_ENTRY" key="4915" >
                <filterList containerType="RSSL_DT_ELEMENT_LIST" countHint="0" flags="0x0">
                    <filterEntry id="3" action="RSSL_FTEA_SET_ENTRY" flags="0x0" containerType="RSSL_DT_ELEMENT_LIST">
                        <elementList flags="0x8 (RSSL_ELF_HAS_STANDARD_DATA)">
                            <elementEntry name="Group" dataType="RSSL_DT_BUFFER" data="2"/>
                            <elementEntry name="MergedToGroup" dataType="RSSL_DT_BUFFER" data="0"/>
                        </elementList>
                    </filterEntry>
                </filterList>
            </mapEntry>
        </map>
    </dataBody>
</updateMsg>

After the service is up, the application will get a new groupID in the item's refresh message.

Therefore, it could be the default groupID managed by TREP. You can contact the TREP support team through my.refinitiv.com for more information.