Which package is mkfs in?

G3zz · January 23, 2023, 3:28pm

Hi,
I found myself needing to quickly create an ext4 filesystem on nix-darwin. Is there a specific nix package that contains mkfs.ext4? (I have an aarch64-linux remote builder set up).

Thanks!

NobbZ · January 23, 2023, 3:49pm

Seems to live in e2fsprogs:

command-not-found mkfs.ext4
$ The program 'mkfs.ext4' is not in your PATH. You can make it available in an
ephemeral shell by typing:
  nix-shell -p e2fsprogs

And darwin even seems to be a supported output:

$ nix eval nixpkgs\#e2fsprogs.meta.platforms --json | jq '.[] as $k | $k' --raw-output|rg darwin
x86_64-darwin
i686-darwin
aarch64-darwin
armv7a-darwin

G3zz · January 23, 2023, 3:55pm

That command-not-found is a nifty thing to know about, thanks!
I guess I can enable it by putting the below in my flake:

config.programs.command-not-found.enable = true;

In the meantime, you’ve answered my original question - thanks very much

NobbZ · January 23, 2023, 4:07pm

It isn’t that easy on flakes, you either need to maintain a nixos channel owned by the root user that points to an actual upstream channel containing the cnf database (the nixos- prefixed ones).

Or use the flake-programs-sqlite as a flake input and make it the used database:

github.com

NobbZ/nixos-config/blob/c82fa2d649ef67b06beebe2e9d804653c1aa7812/flake.nix#L12-L13

    
      
          inputs.programsdb.url = "github:wamserma/flake-programs-sqlite";
          inputs.programsdb.inputs.nixpkgs.follows = "unstable";

github.com

NobbZ/nixos-config/blob/c82fa2d649ef67b06beebe2e9d804653c1aa7812/nixos/modules/flake.nix#L24

    
      
          }: let
            base = "/etc/nixpkgs/channels";
            nixpkgsPath = "${base}/nixpkgs";
            nixpkgs2105Path = "${base}/nixpkgs2105";
            nixpkgs2111Path = "${base}/nixpkgs2111";
            nixpkgs2205Path = "${base}/nixpkgs2205";
          in {
            options.nix.flakes.enable = lib.mkEnableOption "nix flakes";
          
          
  config = lib.mkIf config.nix.flakes.enable {
              programs.command-not-found.dbPath = programsdb.packages.${pkgs.system}.programs-sqlite;
          
          
    nix = {
                package = lib.mkDefault nix.packages.${pkgs.system}.nix; # pkgs.nixUnstable;
                settings.experimental-features = ["nix-command" "flakes"];
          
          
      registry.nixpkgs.flake = unstable;
                registry.nixpkgs2105.flake = nixpkgs-2105;
                registry.nixpkgs2111.flake = nixpkgs-2111;
                registry.nixpkgs2205.flake = nixpkgs-2205;

Sandro · January 24, 2023, 9:41am

Platforms is not a strong indication for “supported”. For example armv7a-darwin is not a thing to my knowledge. It could entirely be the case that unix was slapped on and so far no one used it on darwin.

NobbZ · January 24, 2023, 10:00am

“Supported” in the sense that nix will not complain about “unsupported system” and it will at least try to build

I totally see why you are clarifying this here. And I really wish there was an easy way to check whether a certain attribute builds on linux and/or darwin on hydra…

Sandro · January 24, 2023, 2:43pm

there is https://github.com/nix-community/hydra-check

NobbZ · January 24, 2023, 2:58pm

I’m aware, though it doesn’t eem to build nix for aarch64-darwin, which I know is a lie:

$ hydra-check --arch=aarch64-darwin nix
Build Status for nixpkgs.nix.aarch64-darwin on unstable
⚠ This job is not a member of the latest evaluation of its jobset. This means it was removed or had an evaluation error.