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
               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
               This  command takes an ASCII string argument, the hook name, and clears the statistics associated
               with the hook.

       NGM_HOLE_GETCLR_STATS
               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>

Debian                                            May 19, 2004                                        NG_HOLE(4)