Re: XDG_... env variables in root

[Hamzeh Nasajpour]

Hi,

https://unix.stackexchange.com/questions/7013/why-do-we-use-su-and-not-just-su/7021#7021

>su - invokes a login shell after switching the user. A login shell resets most 
>environment variables, providing a clean base.

>su just switches the user, providing a normal shell with an environment nearly 
>the same as with the old user.


Seems that this is relevant to way of switching user which I used. I was using 
`su` for switching as `root` and just now I found that there are some 
differences between `su` and `su -`. With using of `su -` the `XDG_...` env 
paths are correct:

```
$ su -
$ printenv | grep XDG_
XDG_CONFIG_DIRS=/run/current-system/profile/etc/xdg:/root/.guix-profile/etc/xdg:/run/current-system/profile/etc/xdg
XDG_DATA_DIRS=/run/current-system/profile/share:/root/.guix-profile/share:/run/current-system/profile/share
```

Anyway I didn't know there are differences between `su` and `su -`. 

Regards,
Hamzeh