Fedora and scanners

If you are running Fedora and you want to use a scanner, you probably already have sane (backends at least) and simple-scan installed.

What is incredibly frustrating is when scanimage -L shows you the scanner, but simple-scan does not list it.

What you are missing is

sudo dnf install libnsl

This package is different from libnsl2, which is probably already installed. But some applications must depend on libnsl, including simple-scan. Thanks to suspiciousmilk of Ask Fedora.



  1. Brother scanner driver don’t work [ask.fedoraproject.org]

dnf install build deps

If you want to build a package, but need all of its buildrequires packages, use this command:

sudo dnf builddep wxGTK3

I leave my source repositories off, so be sure to do any –enablerepo=fedora-source,updates-source as necessary.

For debian family

Try a cool tool named “mk-build-deps” as documented over at https://www.guyrutenberg.com/2017/09/23/use-mk-build-deps-instead-of-apt-get-build-dep/



Automatically install build dependencies prior to building an RPM package [stackoverflow.com]

Dnf ignore weak dependencies


dnf --setopt=install_weak_deps=False --best install newpackage

dnf do not install weak dependencies

In the new paradigm for rpm package management (rpmpm?), we use dnf. I am fine with using the latest and greatest, but sometimes yum looks nicer in hindsight than dnf.

One of the more recent features added to rpms is weak dependencies. Debian has had weak dependencies for a longer time, so it’s nice to see rpm adding such a feature.

I recently went through a spell where I wanted to install my own package but exclude the recommended options.

After a lot of research and man dnf dnf.conf, I derived the command I needed.

dnf --setopt=install_weak_deps=False --best install newpackage


I tried an ugly hack, which technically worked.

dnf --disablerepo=* install ./bgscripts*

But all it does is disable all repos. I was using a local file, so it could get to the rpm I required, but any hard dependencies would be not found. I then tried another option, which technically worked.

dnf install ./bgscripts* -x freerdp

But I had to run a dnf command to see what packages would be installed, and then manually named the packages in the exclude list.



  1. https://fedoraproject.org/wiki/PackagingDrafts/WeakDependencies
  2. https://www.debian.org/doc/debian-policy/ch-relationships.html

Man pages