Unclear bug when using a unix:// store

[fzakaria]

Describe the bug

I would like to test chaining stores (what a neat concept!) but I ran into a weird issue as soon as I tried this.

(note: the "unexpected errors happen after I Ctrl-C. The weird issue is the ever increasing PID when trying to do a nix-build against this daemon)

Steps To Reproduce

In one terminal run the following

> NIX_DAEMON_SOCKET_PATH=/tmp/nix_socket nix daemon --debug

In another terminal run:

> nix build nixpkgs#hello --store unix:///tmp/nix_socket

Expected behavior

It should build by propagating through this interim daemon which itself forwards to my local daemon (NixOS)

Metadata

nix-env (Nix) 2.28.3

Checklist

• checked latest Nix manual (source)
• checked open bug issues and pull requests for possible duplicates

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[fzakaria]

I think this has to do with the fact I started the daemon as non-root

When I changed to the following it worked (separate store):

NIX_DAEMON_SOCKET_PATH=/tmp/nix_socket nix daemon --debug --store /tmp/chain
accepted connection from pid 61705, user fmzakari (trusted)
executing Nix database schema migration '20220326-ca-derivations'...
received daemon op 19

Seems like something isn't caught and instead the daemon endlessly tries to build.