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Re: [LUG] Permissions problem

 

NW wrote:
> 
> Well, so far all else has failed, so can anyone tell me how to configure
> udev so that I get the right permissions on lp0? This seems to be my
> only option. I just can't see that I have made any changes to how
> printing works for me, yet it suddenly went wrong!!

Something like - as root...

# ls -l /dev/lp0

# echo 'KERNEL=="lp0", SUBSYSTEM=="printer", MODE="0666"'
>>/etc/udev/rules.d/99-local.rules

# udevadm trigger

# ls -l /dev/lp0

Which puts a new rule in for the device, and causes it to be reloaded.

See http://reactivated.net/writing_udev_rules.html if that doesn't "just
work".

But I have to confess I've never needed to do this in anger since udev
was introduced*. Which should tell you something given this is part of
my day job. The default for all devices is 0660, so it is very unlikely
that a change to the permissions of /dev/lp0 is the cause of the
problem, far more likely you told the software to do this with the wrong
username, or  possibly you installed some printer related software which
broke stuff.

If I were you I'd be checking access times on /etc/cups/cupsd.conf and
comparing it to the default.

Also check say dpkg log and see if you have installed something you
forgot about or installed a security fix.

 Simon

* Actually I have a blog entry about a bug in "cu" where you can't run
it as root, which I think I could workaround with udev, but I filed a
bug report instead. But it makes the point this is relatively obscure
stuff just to get printing working again.

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