[xubuntu-users] Detecting login name after su

[Kevin O'Gorman]

On Fri, Oct 4, 2013 at 6:12 AM, ABIX Adam Jurkiewicz
<a.jurkiewicz at abix.info.pl> wrote:
> Dnia 2013-10-03, czw o godzinie 20:14 +0100, Peter Flynn pisze:
>> Does anyone know how a bash script can detect what username you
>
> just grep your environment:
>
> adasiek at adasiek-ThinkPad-T410:~/Dokumenty$ sudo -i
> [sudo] password for adasiek:
> root at adasiek-ThinkPad-T410:~# env | grep SUDO
> SUDO_USER=adasiek
> SUDO_UID=1000
> SUDO_COMMAND=/bin/bash
> SUDO_GID=1000
>

That looked interesting so I tried it.  It works as you showed, but
the OP also mentioned another way in, where it does not work:

kevin at treat:~$ sudo su -
root at treat:~# env | grep SUDO
root at treat:~# env | wc -l
20
root at treat:~# env | grep kevin
XAUTHORITY=/home/kevin/.Xauthority
root at treat:~#

And indeed the environment in that was is quite impoverished,
containing just 20 lines, mostly very familiar.  LOGNAME was root. The
only one with a hint of the original account is XAUTHORITY, and I have
no idea how reliable that is.

-- 
Kevin O'Gorman

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