[thirdparty/systemd.git] / udevd.8

.TH UDEVD 8 "February 2004" "" "Linux Administrator's Manual"
.SH NAME
udevd \- udev event serializer daemon
.br
udevsend \- sends the event to udevd
.SH SYNOPSIS
.BI udevsend " hotplug-subsystem"
.sp
The environment must provide the following variables:
.TP
.B ACTION
.IR add " or " remove
signifies the connection or disconnection of a device.
.TP
.B DEVPATH
The sysfs devpath of the device without the mountpoint but a leading slash.
.TP
.B SEQNUM
The sequence number of the event provided by the kernel.
If unset, the event bypasses the queue and will be executed immediately.
.SH "DESCRIPTION"
.B udevd
allows the serialization of
.BR hotplug (8)
events. The events generated by the kernel may arrive in random order
in userspace, that makes it neccessary to reorder it.
.br
.B udevd
takes care of the kernel supplied sequence number and arranges the events for
execution in the correct order. Missing sequences are delaying the
execution of the following events until a timeout of a maximum of 5 seconds
is reached.
.br
For each event a
.BR udev (8)
instance is executed in the background. All further events for the same device
are delayed until the execution is finished. This way it will never run more
than one instance for a single device at the same time.
.br
.B udevd
receives the events from
.B udevsend
which is called by
.BR hotplug (8).
If
.B udevd
isn't already running,
.B udevsend
will start it.
.SH "SEE ALSO"
.BR udev (8),
.BR udevinfo (8),
.BR hotplug (8)
.SH AUTHORS
.B udevd
was developed primarily by Kay Sievers <kay.sievers@vrfy.org>, with much help
from others.
Commit	Line	Data
7dae391f KS	1	.TH UDEVD 8 "February 2004" "" "Linux Administrator's Manual"
	2	.SH NAME
	3	udevd \- udev event serializer daemon
	4	.br
	5	udevsend \- sends the event to udevd
bef370d6 KS	6	.SH SYNOPSIS
	7	.BI udevsend " hotplug-subsystem"
	8	.sp
	9	The environment must provide the following variables:
	10	.TP
	11	.B ACTION
	12	.IR add " or " remove
	13	signifies the connection or disconnection of a device.
	14	.TP
	15	.B DEVPATH
	16	The sysfs devpath of the device without the mountpoint but a leading slash.
	17	.TP
	18	.B SEQNUM
	19	The sequence number of the event provided by the kernel.
	20	If unset, the event bypasses the queue and will be executed immediately.
7dae391f KS	21	.SH "DESCRIPTION"
	22	.B udevd
	23	allows the serialization of
	24	.BR hotplug (8)
	25	events. The events generated by the kernel may arrive in random order
	26	in userspace, that makes it neccessary to reorder it.
	27	.br
	28	.B udevd
	29	takes care of the kernel supplied sequence number and arranges the events for
	30	execution in the correct order. Missing sequences are delaying the
	31	execution of the following events until a timeout of a maximum of 5 seconds
	32	is reached.
	33	.br
	34	For each event a
	35	.BR udev (8)
	36	instance is executed in the background. All further events for the same device
	37	are delayed until the execution is finished. This way it will never run more
ad63031e	38	than one instance for a single device at the same time.
7dae391f KS	39	.br
	40	.B udevd
	41	receives the events from
	42	.B udevsend
	43	which is called by
ad63031e KS	44	.BR hotplug (8).
	45	If
	46	.B udevd
	47	isn't already running,
	48	.B udevsend
	49	will start it.
7dae391f	50	.SH "SEE ALSO"
bef370d6 KS	51	.BR udev (8),
	52	.BR udevinfo (8),
	53	.BR hotplug (8)
7dae391f KS	54	.SH AUTHORS
	55	.B udevd
	56	was developed primarily by Kay Sievers <kay.sievers@vrfy.org>, with much help
	57	from others.