Re: pkg(8): difference between "-c /path" and "-r /path"

On Sun, Feb 26, 2023 at 10:07:14AM +0100, Michael Schuster wrote:
> Hi,
> 
> This question is (as of yet) more of the "fill in background info" type:
> From the "pkg(8)" man-page:
> 
>      -c <chroot path>, --chroot <chroot path>
>     pkg will chroot in the <chroot path> environment.
> 
>      -r <root directory>, --rootdir <root directory>
>     pkg will install all packages within the specified <root
>     directory>.
> 
> up to now, I've leaned towards "pkg -c /path <cmd>" when
> installing/updating a BE mounted at /path, but, given some results in the
> past that weren't quite clear to me (yes, that's a bit vague, sorry), I've
> been wondering whether "-r /path" would have been better.
> 
> I'd appreciate thoughts/advice/comments, TIA
> Michael

pkg -c will chroot (real chroot as in chroot(2)) into the directory at early
stage and execute everything from the inside.

This means that for post install script the kernel of the host needs to be able
to run the binary withing the guest (for instance you cannot cross install).

For the packages themselves it is transparent if that is the case.

pkg -r, will run everything from the host and with the provided rootdir prepend
to all path in the packages and database, post install scripts needs to know
about PKG_ROOTDIR variable (which is not the case for many of them in the ports
tree). triggers will be deffered (to be run at next boot).

pkg -r allows cross installation (preparing an arm64 rootdir on a amd64 host).

In long term pkg -r is preferred, right now pkg -c is probably most of the time
safest.

Best regards,
Bapt