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Clients observe the state of component instances and might display this state to the user. Clients can actively query this state from the components, so they need to know when the state is updated.
While the simulation time is progressing, the state of all component instances might change spontaneously and continuously. No special notifications are sent about any state changes, although some instances support event sources to inform clients about events.
All clients register for
IRIS_SIMULATION_TIME_EVENT. When this event is received with a value
RUNNING=False, this indicates that the simulation
time has stopped progressing. Clients should then query all displayed state and
update their views.
While the simulation time is stopped, clients can modify the state of
a component instance, for example by writing resources or memory. Other clients
should register for the
IRIS_STATE_CHANGED event to
get notification of these changes, to update their views. When a client calls a
state-modifying function like
IRIS_STATE_CHANGED event is automatically generated. The client does
not need to generate it. See 4.13.1 Event source IRIS_STATE_CHANGED.