Document/resolve issues around ldconfig

[coderfromhere]

Hi!

The current nixery-based containers lack clarity around ldconfig specifics in Nix, which breaks software tooling expectations, that are usually met within conventional Linux distributions.

For instance, consider the Haskell Stack

[nix-shell:~]$ docker pull nixery.dev/shell/which/stack
Using default tag: latest
latest: Pulling from shell/which/stack
30c2bb75530a: Already exists
7136e5cc50ea: Already exists
333aaab6b4a1: Already exists
efe17156a3d6: Already exists
45fc043ad328: Already exists
54a51240f00f: Already exists
2b2a94a9c2ac: Pull complete
1bc8b8c6cae2: Pull complete
91a928676b9e: Pull complete
b07e29fa0502: Pull complete
0a784a79a191: Pull complete
09259e745068: Pull complete
4ec6623f7ad6: Pull complete
c1ed86da2256: Pull complete
684161f3169c: Pull complete
cefc7fc57a1a: Pull complete
d01d0e2611aa: Pull complete
a73958149f6d: Pull complete
Digest: sha256:0837a346eceb20e5a58d6fd130e77c7a5962c5edc14191168d6a1e8157f995c0
Status: Downloaded newer image for nixery.dev/shell/which/stack:latest
nixery.dev/shell/which/stack:latest

[nix-shell:~]$ docker run -ti nixery.dev/shell/which/stack bash
bash-4.4# which stack
/bin/stack
bash-4.4# which ldconfig
which: no ldconfig in (/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin)
bash-4.4# stack build servant-server
Writing implicit global project config file to: /.stack/global-project/stack.yaml
Note: You can change the snapshot via the resolver field there.
Using latest snapshot resolver: lts-15.1
Stack has not been tested with GHC versions above 8.6, and using 8.8.2, this may fail
Executable named ldconfig not found on path: ["/sbin","/usr/sbin","/usr/local/sbin","/usr/local/bin","/usr/sbin","/usr/bin","/sbin","/bin"]

The error is persistent even if glibc is explicitly present in nixery suffix (e.g. /shell/which/glibc/stack)

[tazjin]

Hey!

Thanks for reporting this, I believe this also falls under #58 (i.e. creating an FHS symlink layer instead of the current plain one).

Considering that there are now several issues blocked on that particular thing, I'll prioritise getting it done in the next couple of days!

[coderfromhere]

Hi @tazjin ! Thanks for the fast feedback, I agree on the premise, #58 does look like a possible solution.