How can I update sane-backends for Ubuntu 20.04?

reducing activity

5/8/24, 10:55 AM

scanimage --version shows

scanimage (sane-backends) 1.0.29; backend version 1.0.29

which is ancient and may be reason why I get cryptic failures like scanimage: sane_read: Error during device I/O - for CanonScan Lide 300 listed as supported on http://www.sane-project.org/sane-mfgs.html

(In case of XY problem: I am fine also with getting scanner to work in other way, or at least to produce less cryptic errors)

120

1 + 2

sane

scanner

20.04

user535733

5/8/24, 3:13 PM

LTS releases do not generally get new versions, unless required for security. That lack of change is their main feature, not a bug. You are using a 3-year-old version of `sane-backends` because you are running a 3-year-old OS. Consider testing a newer release of Ubuntu, which has newer `sane-backends` that --as you have already discovered-- solve your specific cause.

reducing activity

5/9/24, 5:04 PM

@user535733 That gets you with release treadmill and need to install new system versions quite often (sometimes when you really need to do something else)

Score:1

Ubuntu

reducing activity

5/8/24, 11:02 AM

You can try release-upgrade and maybe next OS version has newer package. Note that of you leave LTS version you may need to repeat release-upgrade more often.

sudo add-apt-repository ppa:sane-project/sane-release
sudo apt update
sudo apt install libsane libsane-common sane-utils

based on https://gitlab.com/sane-project/backends/-/tree/master fixed the problem - not sure is there a way to do this without an extra ppa

Now I have 1.2.1-debian backend and [13:00:45.703111] [pixma] device response: ScannerCarriageLockError - Please consult the manual to unlock the Carriage Lock. as a new hint - which indicated that I need to use special unlock button at the bottom of the scanner.

Note that installing bunch of PPA may make future release-upgrade harder - but it is not relevant if you reinstall rather upgrading.

+ 5

user535733

5/8/24, 3:09 PM

Future readers should keep in mind that this answer works only temporarily, and you won't find much support if it breaks. Adding new (wrong-version) packages to an older LTS creates a [FrankenDebian](https://wiki.debian.org/DontBreakDebian#Don.27t_make_a_FrankenDebian), which often leads down the path to a self-inflicted broken system. Folks discover this during their *next* install or release-upgrade, months (years) after they unknowingly caused the problem.

reducing activity

5/9/24, 5:03 PM

@user535733 My strategy is to reinstall system, and I never do `release-upgrade` (this allows me to verify that backup strategy and Ansible system-state are working well, with older system state preserved on backup drive so files/programs/settings missed by my backup/restore scripts can be added)

reducing activity

5/9/24, 5:04 PM

@user535733 Though if there is a better alternative then I would be happy to learn about it

user535733

5/9/24, 6:18 PM

Since you intend to reinstall, the shortcoming of this method seems irrelevant. Do it and enjoy! Folks who intend to release-upgrade should avoid this method, and simply release-upgrade sooner (instead of later) to get the newer software in a later release of Ubuntu.

reducing activity

5/9/24, 6:22 PM

@user535733 Noted both in my answer.

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