From FIXwiki

FIX Message TradingSessionStatusRequest (MsgType=g)

MsgType	FIX Specification	First introduced	Deprecated
MsgType=g	PreTrade messages - MarketStructureReferenceData	FIX.4.2

The Trading Session Status Request is used to request information on the status of a market. With the move to multiple sessions occurring for a given trading party (morning and evening sessions for instance) there is a need to be able to provide information on what product is trading on what market.

The Trading Session Status Request message can be used to inquire the trading status of a trading party. The Trading Session Status message can be used to subscribe to updates to the status of a trading session by setting the RequestType field to 1.

To list the securities available during a particular trading session, see the SecurityDefinitionRequest message.

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Notes

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