This read-only integer returns the line number associated with the SNMP table whose object identifier is given by the entry's rcSnmpTableObjectID index. It lets management tools determine a table's line count via SNMP by supplying that table's OID as the index, instead of having to enumerate the table's rows directly. For example, looking up this object using the OID of a vendor-specific configuration table might return a value such as 12, indicating that table currently holds 12 lines.