On 2023-12-15 15:56:34 +0100, Kristoffer Ström wrote:
>
> Hello! I'm running emacs in a guix shell, and wonder how/where to get
> the C source code directory for xref-find-definitions.
>
> I've grepped the /gnu/store/*emacs but cannot find the C source, is
> there some special package/output or procedure needed to get it included
> in the shell environment?

You can download source archives for any package using build --sources, like
this:

    $ guix build --sources emacs
    substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0%
    43.3 MB will be downloaded:
      /gnu/store/c4xfnis0g5g2v1ssl3wqgk8h6s3xjfk6-emacs-29.1.tar.xz
    substituting /gnu/store/c4xfnis0g5g2v1ssl3wqgk8h6s3xjfk6-emacs-29.1.tar.xz...
    downloading from https://bordeaux.guix.gnu.org/nar/lzip/c4xfnis0g5g2v1ssl3wqgk8h6s3xjfk6-emacs-29.1.tar.xz ...
     emacs-29.1.tar.xz  41.3MiB                                                                                                                         16.6MiB/s 00:02 ▕██████████████████▏ 100.0%

    /gnu/store/c4xfnis0g5g2v1ssl3wqgk8h6s3xjfk6-emacs-29.1.tar.xz

You can then extract the archive somewhere.

Hope this helps,
Tomas

--
There are only two hard things in Computer Science:
cache invalidation, naming things and off-by-one errors.