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ng_hole — netgraph discard node type
#include <sys/types.h> #include <netgraph/ng_hole.h>
The hole node type silently discards all data and control messages it receives. This type is used for testing and debugging.
A ng_hole node accepts any request to connect, regardless of the hook name, as long as the name is unique.
This node type supports the generic control messages, plus the following: NGM_HOLE_GET_STATS (getstats) This command takes an ASCII string argument, the hook name, and returns the statistics associated with the hook as a struct ng_hole_hookstat. NGM_HOLE_CLR_STATS (clrstats) This command takes an ASCII string argument, the hook name, and clears the statistics associated with the hook. NGM_HOLE_GETCLR_STATS (getclrstats) This command is identical to NGM_HOLE_GET_STATS, except that the statistics are also atomically cleared.
This node shuts down upon receipt of a NGM_SHUTDOWN control message, or when all hooks have been disconnected.
The ng_hole node type was implemented in FreeBSD 4.0.
Julian Elischer <julian@FreeBSD.org>