[systemd-devel] udev rules environment variable

[Kay Sievers]

On Tue, Dec 17, 2013 at 2:05 PM, Robert Milasan <rmilasan at suse.com> wrote:
> On Tue, 17 Dec 2013 13:54:34 +0100
> "Martin Pitt" <martin.pitt at ubuntu.com> wrote:
>
>> Robert Milasan [2013-12-17 12:44 +0100]:
>> > I have this rule as a test, but doesn't do squat (meaning it doesnt
>> > work) :)
>> >
>> > ACTION=="add", SUBSYSTEM=="net", KERNEL=="?*", ENV{test_device}="1"
>> >
>> > ACTION=="remove", SUBSYSTEM=="net", KERNEL=="?*",
>> > ENV{test_device}=="1", RUN+="/bin/sh -c 'echo test_device
>> > > /tmp/test_device.log'"
>>
>> Drop the KERNEL== bits. Network devices don't have a /dev/... device
>> node in Linux, so KERNEL will never be set for those.

KERNEL is the device name in /sys, without the leading path. It is in
almost all cases also the name in /dev, but there are some
differences. And right, it is always set, there is never a point to do
such a match.

> Even without the KERNEL== doesn't seem to work:

It's pointless to match that, so it should not make a difference.

> I'm testing this by first removing the network device (ex. rmmod
> e1000), so I can have first an ADD event and then a REMOVE event, by
> removing again the module, so:
>
> rmmod e1000 (remove first)
> modprobe e1000 (ADD event, set the test_device var to 1)
> rmmod e1000 (REMOVE event, get the test_device value)
>
> This doesn't seem to work, or at least it looks like that.

How old is your udev? You are not possibly talking about years old
versions, right?

Kay