When installing gcc, I try to set the priority, but get the following result:
I searched for examples found a couple, but they seem similar. Is there something I’m doing wrong?
$ nix-env --version
nix-env (Nix) 2.11.1
Related Reading:
What is already installed via nix-env?
Please use nix-env -q to check.
As the message clearly says, that you shall set the priority of the already installed package.
Despite this questions, why are you trying to install gcc at all via nix-env, especially as there seems to be already a gcc available on the system.
Why don’t use the gcc you already have?
It says “of one of the conflicting packages” and lists the not-installed one as conflicting. So I’d have to disagree. If it did say “set the priority of the already installed package” I would’ve known what to do.
Because I want a different version
$ nix-env -iA nixpkgs.THING1
Blah blah priority of `/nix/store/blahblahblah-thing1-0.0.1`
conflicts with `/nix/store/blahblahblah-thing2-2.2.2`
$ nix-env --set-flag priority 9 thing2-2.2.2
$ nix-env -iA nixpkgs.THING1
$ nix-env --set-flag priority 0 thing1-0.0.1
$ nix-env --set-flag priority 10 thing2-2.2.2
It seems rather round-about but I don’t see another way
It says nix-env --set-flag priority NUMBER INSTALLED_PKGNAME…
Then use a nix-shell for the project that requires the different version.