Where should the XDG_CONFIG_HOME variable be defined?

Question

The XDG specification talks about the XDG_CONFIG_HOME variable, but does not specify where it should be defined. Should we define it in /etc/X11/Xsession, or is it the window manager's config file that needs to define this?

I tried declaring it in /etc/environment as

XDG_CONFIG_HOME="$HOME/.config"

but that didn't work, as it seems that $HOME is not defined when /etc/environment is parsed.

The only documentation I could find online was for Gentoo, where it was declared in /etc/env.d/90xsession

I'm using Ubuntu. What would be the general solution for Debian based distros?

Answer 1

In Arch Linux, this is defined by /etc/profile, using a /etc/profile.d script. (I made a list of variables once.)

For Debian/Ubuntu, if there's a /etc/profile.d – create a similar script inside; if such a directory does not exist – edit /etc/profile itsef.

export XDG_CONFIG_HOME="$HOME/.config"

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The /etc/environment file is parsed by pam_env, which treats it as simple name=value assignments. However, it also has /etc/security/pam_env.conf, which supports variable expansion and can be used for this purpose.

Answer 2

You don't need to define it anywhere, unless you want to change the default.

XDG Base Directory Specification clearly says:

If $XDG_CONFIG_HOME is either not set or empty, a default equal to $HOME/.config should be used.

So it is redundant to define it to the default value. All compliant applications will already use $HOME/.config

But, if you do want to change the default in a Debian/Ubuntu system, the best place is:

• For a system-wide change, affecting all users: /etc/profile
• For your user only: ~/.profile