ng_device (4)

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Copyright (c) 2002 Mark Santcroos <marks@ripe.net>

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(The comments found at the beginning of the groff file "man4/ng_device.4freebsd".)

NAME

ng_device - device netgraph node type

SYNOPSIS

In 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

netgraph(4), ngctl(8)

HISTORY

The device node type was first implemented in Fx 5.0 .

AUTHORS

An Mark Santcroos Aq marks@ripe.net An Gleb Smirnoff Aq glebius@FreeBSD.org