hotplugd - devices hot plugging monitor daemon
hotplugd [-d device]
The hotplugd daemon monitors the hotplug(4) pseudo-device,
acting on signaled
events by executing the scripts in the /etc/hotplug
default it uses the /dev/hotplug device for reading events
from, but an
alternative device can be specified with the -d option. Actions can be
configured either for device attachment or detachment. On
the attach script is executed if it exists. On device
the detach script is executed if it exists. In both cases
are passed to the scripts: the class and name of the attached or detached
device. Device class corresponds to the classes described
<sys/device.h> header file and can be one of the following:
0 generic, no special info
1 CPU (carries resource utilization)
2 disk drive
3 network interface
4 tape device
5 serial line interface
Not all classes can be really usable, e.g. it's unlikely to
have a hot
Device name is a usual name including unit number, e.g. sd1.
/dev/hotplug Pseudo-device file.
/etc/hotplug Directory where the scripts to execute
/etc/hotplug/attach Script to execute on device attachment.
/etc/hotplug/detach Script to execute on device detachment.
Sample attach script:
case $DEVCLASS in
# disk devices
disklabel=`/sbin/disklabel $DEVNAME | grep
'^label:' | sed -e 's/^label: //'`
case $disklabel in
# Sony DSC camera
mount /dev/"$DEVNAME"i /mnt/camera
# network devices
The hotplugd program first appeared in OpenBSD 3.6.
The hotplugd program was written by Alexander Yurchenko
OpenBSD 3.6 March 30, 2004
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