why are they named XDG_* like XDG_CONFIG_DIR?

Why not just CONFIG_DIR?

Doesn't matter. This whole situation is a mess, and it's still a mess in the year 2025. Clearly existing operating systems can't be changed significantly enough to change anything like this.

but we're all still afraid to write new operating systems. We cling to MacOS, FreeBSD, Linux, and Windows as if our lives depend on it. Our lives do not depend on it.

If we want a saner OS, we could have it, but we don't want it bad enough, I think. It's easier to just deal with the piles of horse manure that has been piled on top of everything. So we have a rather active bikeshed discussion on HN about whether or not to use XDG_*.

We want to bikeshed more than we want to fix anything. Like all communities, this one also disappoints me.

Can't you just std::env::var it? Why need a library? It's not even set on my MacBook though.

Yeah, the variable is usually unset, so you’ll want to have a default value in your code. Basically something like

  config_dir="${XDG_CONFIG_HOME:-$HOME/.config}/my-app"

Of course, if you decide to account for Windows / macOS conventions, it’ll be a bit trickier, but pulling in a library for that is a bit overkill, yeah.

Adding a library for that is not overkill but just being polite to your users setting files where the OS suggests and not putting your ideas there,

Adding a library has nothing to do with that. You can implement it yourself in a few lines of code, especially if you only need one path, like configs. You do need to research for caveats (e.g. check $XDG_CONFIG_HOME on Linux and not just put it into ~/.config) but it’s not rocket science.

And if you choose to just trust library authors, you are putting their ideas there instead. There’s that Rust crate that uses XDG on macOS, for example.