You can also request information about hardware properties.
These hardware properties are monitored through the sys sudo file system.
And as an easy interface you can use udev ADM info because that will read it
for you and it will get the relevant information. You will notice that this sys file
system can be quite complicated, so better use commands like udev ADM info on DEV cdrom.
Hardware properties may also be set on the drivers.
If that is the case, you can use mod info
that will show you the driver information that is happening.
If, for instance, you want to see what is going on on your
CD ROM device, ModInfo on SR0 should do it. Let me show you.
Let's start at the lower level, which is the driver level where I'm going to use
sudo LSMod, Pipe Grab SR SR is typically your CD ROM device. And oh, I can
see CD ROM, that's the module that I need. Okay, so I'm using multinfo to CD
Rom and there we can see the different parameters that exist for this driver.
So these are parameters that determine the usage of the driver.
Now, for a CD ROM that is not very spectacular, but if you
do the same for a network card like my E1000 there we can
see settings that determine how the network card is working. Like the duplex
setting. That's kind of old, but other settings might be available as well.
Sometimes if there's a problem, then it might be related to the parameters of these drivers.
Now, if you want to know in more detail what is going on, then UDEV adminfo is useful.
Let me use sudo udev adminfo on DEV CDROM for instance.
There we can see all the different properties that I set for this CD ROM device.
Now I'm using the device interface file to get this information.
As you can see on the top line, it is actually using a file that is deeply hidden
into the sys devices directory and all the property of the device device are shown right here.
And I would definitely recommend, if ever you need to know
more about your devices, check it out here. UDEV ADM info
is much more accessible than exploring the sys directory for yourself.