Pkg3: system depot can't live under /usr/julia

[nalimilan]

The /usr directory cannot contain application-specific directories. Also, things under /usr should generally be managed exclusively by distro package managers. So a better place (according to the FHS) would be /usr/local/share/julia for architecture-independent files (like sources), and /usr/local/lib/julia for binaries.

[StefanKarpinski]

I originally had it under /usr/local for the example but changed it.

[StefanKarpinski]

@nalimilan: I changed these to be under /usr/local which doesn't address the architecture-independent vs architecture-dependent issue. Do you have any thoughts on how to best handle that? Symlinks from /usr/local/share/julia/default/libraries to /usr/local/lib/julia/ or something like that?

[nalimilan]

I'd rather say symlinks from /usr/local/lib/julia/ to /usr/local/share/julia/default/libraries, since AFAIK the goal is to share architecture-independent files across different architectures to save some space. Though that's a relatively small optimization, so not as important as storing things under /usr/local in general.

[StefanKarpinski]

Do you want to suggest some wording to that effect to go somewhere in that section?

[nalimilan]

Maybe this: change standard depot path to /usr/lib/julia/, and system depot path to /usr/local/julia/. The four directories listed below are directly under that path; if you prefer, add something like /depot/ to both paths, though I'm not convinced it's needed.

Finally, maybe just mention under the bullet for the libraries directory that it can be a symlink to ../share/julia/libraries. But as I said that's an optimization which is mostly transparent, so not a big deal.

[ararslan]

Just as an additional data point: if I'm not mistaken, /usr directories other than /usr/local are no longer writable on MacOS starting with Sierra (10.12).

[nalimilan]

Everything I wrote is only valid for Linux. I have no idea what happens on Mac. Anyway, the standard depot should probably be installed at the same place as Julia itself.