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Data Distributor is a unix-based event buffer manager. It was originally developed for the AGS rare kaon experiment E787 at BNL. We adopted DD as a part of DAQ using CODA and have converted each component of DAQ(EB,ANA,...) into C program so that DD routine is available. Basically DD uses FIFOs(named pipe),semaphores (resource counter),shared memory(event buffer). To use DD, at first a DD system [Fig.1] must exist. INPUT_FIFO,BRC_FIFO and GARB_FIFO are the default static FIFOs. INPUT_FIFO is used by producer and BRC_FIFO is related to broadcasting which distributes event all over the DD system. Unused events go into GARB_FIFO. Each FIFO has fevs(fifo_entries), which are C structures containing the information about events(size,location in the shared memory,etc)