Hi all： I'm reading the TEP 116 Packet Protocols.
In Section 2.1 there documents the "clear" command of Packet Interface. This command is described as the following: *The ``clear`` command clears out all headers, footers, and metadata* *for lower layers. For example, calling ``clear`` on a routing* *component, such as CollectionSenderC[4]_, will clear out the* *collection headers and footers. Furthermore, CollectionSenderC will* *recursively call ``clear`` on the layer below it, clearing out the* *link layer headers and footers. Calling ``clear`` is typically* *necessary when moving a packet across two link layers. Otherwise, the* *destination link layer may incorrectly interpret metadata from the* *source link layer, and, for example, transmit the packet on the wrong* *RF channel. Because ``clear`` prepares a packet for a particular link* *layer, in this example correct code would call the command on the* *destination link layer, not the source link layer.* TEP116 told us that the clear command is used for clear the header, footer, and meta-data field of the packet. Then I checked the code comments int * $TOSROOT/tos/interface/Packet.nc* about the "clear" command : * /** * * * Clear out this packet. Note that this is a deep operation and* * * total operation: calling clear() on any layer will completely* * * clear the packet for reuse.* * * @param 'message_t* ONE msg' the packet to clear* * */* * command void clear(message_t* msg);* MAY be the TEP116 document is out-of-date? Please update this document if I was right. * *
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