NAME
ng_device —
device netgraph node type
SYNOPSIS
#include
<netgraph/ng_device.h>
DESCRIPTION
A device node is both a netgraph node and
a system device interface. When a device node is
created, a new device entry appears which is accessible via the regular file
operators such as
open(2),
close(2), read(2),
write(2), etc.
The first node is created as /dev/ngd0, all subsequent nodes /dev/ngd1, /dev/ngd2, etc.
HOOKS
A device node has a single hook with an
arbitrary name. All data coming in over the hook will be presented to the
device for read(2). All data coming in from the device entry by
write(2) will be forwarded to the hook.
CONTROL MESSAGES
The device node supports one non-generic
control message:
NGM_DEVICE_GET_DEVNAME- Returns device name corresponding to a node.
SHUTDOWN
This node shuts down upon receipt of a
NGM_SHUTDOWN control message, or upon hook
disconnection. The associated device entry is removed and becomes available
for use by future device nodes.
SEE ALSO
HISTORY
The device node type was first implemented
in FreeBSD 5.0.
AUTHORS
Mark Santcroos
<marks@ripe.net>
Gleb Smirnoff
<glebius@FreeBSD.org>