NAME

ng_hole —

netgraph discard node type

SYNOPSIS

#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>