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NG_HOLE(4) FreeBSD Kernel Interfaces Manual NG_HOLE(4)
NAME
ng_hole - netgraph discard node type
SYNOPSIS
#include <sys/types.h>
#include <netgraph/ng_hole.h>
DESCRIPTION
The hole node type silently discards all data and control messages it
receives. This type is used for testing and debugging.
HOOKS
A ng_hole node accepts any request to connect, regardless of the hook
name, as long as the name is unique.
CONTROL MESSAGES
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.
SHUTDOWN
This node shuts down upon receipt of a NGM_SHUTDOWN control message, or
when all hooks have been disconnected.
SEE ALSO
netgraph(4), ng_echo(4), ngctl(8)
HISTORY
The ng_hole node type was implemented in FreeBSD 4.0.
AUTHORS
Julian Elischer <julian@FreeBSD.org>
FreeBSD 14.0-RELEASE-p11 May 19, 2004 FreeBSD 14.0-RELEASE-p11