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This DSL memory management services allow efficient coordination for both single and multiple I/O transactions to a given buffer. A single transaction--such as reading page-faulted data into a client's memory--uses a PrepareMemoryForIO call before the transfer and a single CheckpointIO call when the transfer is complete. A multiple transaction scenario--such as a network driver that transfers from its own buffers and divides blocks in and out of the client buffer--uses a single PrepareMemoryForIO call during driver initialization and a CheckpointIO call before and after each transfer. The intermediate calls to CheckpointIO would include the kIOMoreTransfers option, so the memory preparation remains in effect.