Derive PATH from the guest OS

[jonashoechst]

Currently, the PATH variable is just copied from the source OS. This works when modifying Debian-based OSss on Debian but fails, when targeting some other OSes.

We should generalize this and maybe provide an option which file to source.

[oxzi]

Guessing the right PATH could be difficult or even unfeasible, e.g., using a plain NixOS image. In general, different target and source systems are hard.

Even sourcing some .bashrc, .zshrc, or .whateverrc file could result in lots of unintended side effects. For example, overwriting other variables or executing unintended code.

Thus, I would recommend adding a PATH command which just overlays the PATH variable for the RUN command.

[oxzi]

As previously discussed, this only works if the guest system uses the same PATH as the host.
However, if necessary, one can source the .bashrc within the image.

Otherwise, there is the PATH command within pimod to overwrite the guest's PATH.