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_BPF_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_BPF_CLR_STATS
- This command takes an ASCII string argument, the
- hook name, and
clears the statistics associated with the hook. - NGM_BPF_GETCLR_STATS
- This command is identical to NGM_BPF_GET_STATS, ex
- cept 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>
- BSD May 19, 2004