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Adding an External Trigger

Typically, a FlowController uses an internal trigger to periodically replenish its tokens. The period by which this trigger is called is determined by the period property setting.

The trigger_flow() function provides an additional, external trigger to the FlowController. This trigger adds tokens_added_per_period tokens each time it is called (subject to the other property settings of the FlowController).

DDS_ReturnCode_t trigger_flow () 

An on-demand FlowController can be created with a DDS_DURATION_INFINITE as period, in which case the only trigger source is external (i.e. the FlowController is solely triggered by the user on demand).

trigger_flow() can be called on both a strict on-demand FlowController and a hybrid FlowController (internally and externally triggered).

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