Cannot install direvent even if it seems well packaged

Help
1

I am unable to install the direvent monitoring daemon – a GNU project that strengthens inotify.

AFAIK direvent seems well packaged though, with its callPackage line in all-packages.nix.

I tried to install it using an up to date nixpkgs local repo

nix-env -iA nixos.direvent -I nixpkgs=/home/<user>/Dev/nixpkgs

without any success. Installing packages, like dejagnu or lattice-diamond (at the same location in nixpkgs), work fine.

What am I missing here ?

EDIT

cd nixpkgs/pkgs/development/tools/misc/direvent
nix-build -E 'with import <nixpkgs> { }; callPackage ./default.nix { }'

works, but I still need the standard way to install direvent for my project.

2

This package is not available in 19.09. You can upgrade to 20.03 however to install it.
It is also possible import a newer nixpkgs tarball in your project’s shell.nix.

3

Even if I use the nixos-unstable branch of nixpkgs-channels repo ?

4

It is in my nixos-unstable channel. Is your nixos-unstable channel out-of-date or do you by chance not the channel you think you use?

5

What is really surprising is that direvent is in my local nixpkgs tree. I can see it. My local nixpkgs is a clone of the nixos-unstable branch of the nixpkgs-channels repository.

Can you install direvent ?

6

Yes, what is the output of nix-shell -p nix-info --run "nix-info -m" on your machine?

7 
 - system: `"x86_64-linux"`
 - host os: `Linux 5.4.30, NixOS, 19.09.2370.e10c65cdb35 (Loris)`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.3.3`
 - channels(jlucas): `"home-manager"`
 - channels(root): `"nixos-19.09.2370.e10c65cdb35"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`
8

You are not using the unstable channel. You are using nixos-19.09.2370.e10c65cdb35

9

I thought that the option -I nixpkgs=/home/<user>/Dev/nixpkgs superseded the configured channel.

10

Yes. If you are using nixos-rebuild or nix-shell. For nix-env use: nix-env -f /home/<user>/Dev/nixpkgs -iA direvent

11

Ok thanks, that works fine :slight_smile:

In nix-env manual I read

Paths added through -I take precedence over NIX_PATH.

thus I thought that it would precede the configured 19.09 nix-channel.
I need to understand more how channels are linked to NIX_PATH I guess.

12

I have also not really understand how channels or nix-env works in detail. I have a nixpkgs checkout in my NIX_PATH and use nixos-rebuild/home-manager.

13

if you pass -I nixpkgs=/home/<user>/Dev/nixpkgs I think you should run nix-env -iA nixpkgs.direvent

14

I tried with nixpkgs.direvent instead of nixos.direvent. Updating to nixos-20.03 solves my issue anyway – even if I still do not fully understand what was wrong.