Where to set XDG_CACHE_HOME?

[Duncan]

Marek Greško posted on Thu, 12 Mar 2026 05:57:49 +0000 as excerpted:

> unfortunately, also after reboot there is no progress in this matter. I
> also tried to define MESA_SHADER_CACHE_DIR before reboot, but also no
> luck.
> 
> Either the file is ignored, or it is not soon enough processed, or mesa
> ignores the setting in some situations. But I think the last one is not
> the right one, because I found some drkonqi files also in the .cache
> directory yesterday. So this points to timing again.

It occurs to me there's yet another option available, the PAM login 
authentication mechanisms environment module that sets stuff like a basic 
PATH, even if a user's normal environment setting is skipped/broken.  
Again I've never had to mess with it much myself (mostly only looked at it 
from time to time to satisfy my curiosity), and because it's 
authentication, you'll want to take care with experiments (like editing 
/etc/sudoers, don't lock yourself out with a bad config and don't test on 
a deployed production system... unless you're prepared to reboot it to 
backups for recovery!), but PAM *does* have an environment-setup module, 
that you could probably put your XDG_* vars in too.  AFAIK that actually 
runs at the PAM level as part of the authentication, even before the 
systemd user session stuff I believe, so you can't get any earlier than 
that unless you arrange to put it in the system config not the user 
config.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman