[Quickfix-developers] How to reset the session only at start time

[Alain T. <a....@ne...>]

Hi,

I'm on the initiator side and I have problems to get this behavior with quickfix (C++ and .Net wrappers)

- the initiator resets the connexion at start time (MsgSeqNum=1, ResetSeqNumFlag=Y)
- it does not resets the connection at other times like a logon after a disconnection

When I set "reset on logon" at true the flag is set but it also resets sessions if it reconnects
during the day (similar issues with the two other "reset on" settings)

When I set the flags to false, the session is reset at start time, but ResetSeqNumFlag is missing.


According to the source code, this flag is never set if these settings are disabled:

bool Session::shouldSendReset()
{ QF_STACK_PUSH(Session::shouldSendReset)

  std::string beginString = m_sessionID.getBeginString();
  return beginString >= FIX::BeginString_FIX41
    && ( m_resetOnLogon || 
         m_resetOnLogout || 
         m_resetOnDisconnect )
    && ( getExpectedSenderNum() == 1 )
    && ( getExpectedTargetNum() == 1 );

  QF_STACK_POP
}


According to this comment in the FIX 4.4 spec, I don't see when a logon message can have MsgSeqNum=1 and not the tag ResetSeqNumFlag.


" ... the initiator should send a Logon with ResetSeqNumFlag set to Y and with MsgSeqNum of 1. The acceptor
should respond with a Logon with ResetSeqNumFlag set to Y and with MsgSeqNum of 1. At this point
new messages from either side should continue with MsgSeqNum of 2. It should be noted that once the
initiator sends the Logon with the ResetSeqNumFlag set, the acceptor must obey this request and the 
message with the last sequence number transmitted "yesterday" may no longer be available. The
connection should be shutdown and manual intervention taken if this process is initiated but not followed
properly."


Thanks for any hint !


-- 

Alain Tésio
Nexfi