Scanner / SANE driver support

Scanner / SANE driver support

[Pierre Neidhardt]

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Hi!

I'm trying to installer a scanner on Guix System and

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scanimage -L
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does not find anything.

A few drivers are available in sane-backends.
I've enabled the sane-service.

Questions:

- Are we supposed to add the desired users to the 'scanner' group?

- How are the backends found?  I don't see any environment variable.
  According to https://nixos.wiki/wiki/Scanners, SANE would look up
  LD_LIBRARY_PATH.

Any success running scanners on Guix?

-- 
Pierre Neidhardt
https://ambrevar.xyz/

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Re: Scanner / SANE driver support

[sirgazil]

 ---- On Sun, 19 Apr 2020 18:39:30 +0000 Pierre Neidhardt <mail@ambrevar.xyz> wrote ----
 > Hi!
 > 
 > I'm trying to installer a scanner on Guix System and
 > 
 > --8<---------------cut here---------------start------------->8---
 > scanimage -L
 > --8<---------------cut here---------------end--------------->8---
 > 
 > does not find anything.
 > 
 > A few drivers are available in sane-backends.
 > I've enabled the sane-service.
 > 
 > Questions:
 > 
 > - Are we supposed to add the desired users to the 'scanner' group?
 > 
 > - How are the backends found?  I don't see any environment variable.
 >   According to https://nixos.wiki/wiki/Scanners, SANE would look up
 >   LD_LIBRARY_PATH.
 > 
 > Any success running scanners on Guix?

Yes. I use a scanner and I don't have to add anything special to my OS configuration. I just start Simple Scan, and the application detects the scanner. My user is not in the "scanner" group.

But the scanner works like this only recently. Before, I had to follow these instructions: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=38064#11

Also, check that all cables are plugged properly.

Re: Scanner / SANE driver support

[Pierre Neidhardt]

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sirgazil <sirgazil@zoho.com> writes:

> But the scanner works like this only recently. Before, I had to follow these instructions: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=38064#11

As far as I understand, we now have a sane-service-type as part of the
%desktop-services, so this should work out of the box.

> Also, check that all cables are plugged properly.

lsusb reports my scanner.

-- 
Pierre Neidhardt
https://ambrevar.xyz/

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Re: Scanner / SANE driver support

[Pierre Neidhardt]

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sane-service-type seems to only support the minimal backends package:

--8<---------------cut here---------------start------------->8---
(define sane-service-type
  (service-type
   (name 'sane)
   (description
    "This service provides access to scanners @i{via}
@uref{http://www.sane-project.org, SANE} by installing the necessary udev
rules.")
   (default-value sane-backends-minimal)
   (extensions
    (list (service-extension udev-service-type list)
          (service-extension account-service-type
                             (const %sane-accounts))))))
--8<---------------cut here---------------end--------------->8---

The value of the service is a single package, not a list of packages.
So how does one add support for other scanner?

-- 
Pierre Neidhardt
https://ambrevar.xyz/

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Re: Scanner / SANE driver support

[Pierre Neidhardt]

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I believe another reason why our current sane service would not work for
extra backends is because we need to populate etc/sane.d/dll.conf with the
new backends.  Or maybe etc/sane.d/dll.d/.  To be confirmed.

-- 
Pierre Neidhardt
https://ambrevar.xyz/

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