SNMP: index into snmpCommunityTable

[gfoley]

Hi

I want to reset the read and write community strings (public, private) using snmp set. To do this I need to index into (or walk) the snmpCommunityTable in the SNMP-COMMUNITY-MIB. Does anyone know how to
a) differenciate between read and write strings and their respective rows
b) index to that row of the table if the snmpCommunityIndex is not set or unknown ??

Thanks
Gráinne