freebsd man page for ng_tee

NG_TEE(4)						   BSD Kernel Interfaces Manual 						 NG_TEE(4)

NAME
     ng_tee -- netgraph ``tee'' node type

SYNOPSIS
     #include <sys/types.h>
     #include <netgraph/ng_tee.h>

DESCRIPTION
     The tee node type has a purpose similar to the tee(1) command.  Tee nodes are useful for debugging or ``snooping'' on a connection between
     two netgraph nodes.  Tee nodes have four hooks, right, left, right2left, and left2right.  All data received on right is sent unmodified to
     both hooks left and right2left.  Similarly, all data received on left is sent unmodified to both right and left2right.

     Packets may also be received on right2left and left2right; if so, they are forwarded unchanged out hooks right and left, respectively.

HOOKS
     This node type supports the following hooks:

     right	 The connection to the node on the right.

     left	 The connection to the node on the left.

     right2left  Tap for right to left traffic.

     left2right  Tap for left to right traffic.

CONTROL MESSAGES
     This node type supports the generic control messages, plus the following.

     NGM_TEE_GET_STATS (getstats)
	  Get statistics, returned as a struct ng_tee_stats.

     NGM_TEE_CLR_STATS (clrstats)
	  Clear statistics.

SHUTDOWN
     This node shuts down upon receipt of an NGM_SHUTDOWN control message, or when all hooks have been disconnected.  If both right and left hooks
     are present, node removes itself from the chain gently, connecting right and left together.

SEE ALSO
     tee(1), netgraph(4), ngctl(8)

HISTORY
     The ng_tee node type was implemented in FreeBSD 4.0.

AUTHORS
     Julian Elischer <julian@FreeBSD.org>

BSD
								   May 28, 2004 							       BSD