OnixS C++ FIX Engine  4.10.1
API Documentation
Resetting Message Sequence Numbers

OnixS::FIX::Session class exposes OnixS::FIX::Session::resetLocalSequenceNumbers member to reset both incoming and outgoing local message sequence numbers to 1 and back up the previous log files.

Note
OnixS::FIX::Session::resetLocalSequenceNumbers member can be called only when the session is disconnected.