> I recently installed Xubuntu 12.04 on my home desktop where I was
> previously running Ubuntu 10.10, and something strange is now
> happening - who and write don't work the way they used to.
I am not sure about what is meant for "the way they used to".
Nevertheless, this is a known issue on LightDM ; a patch has been
proposed and accepted upstream, and a SRU is opened against 12.04, with
a target of 12.04.1.
> 1) 'who' by itself displays nothing at all. With 'who -a', I get
> $ who -a
> system boot 2012-06-16 12:57
> run-level 2 2012-06-16 12:57
> LOGIN tty4 2012-06-16 12:57 1081 id=4
> LOGIN tty5 2012-06-16 12:57 1087 id=5
> LOGIN tty2 2012-06-16 12:57 1094 id=2
> LOGIN tty3 2012-06-16 12:57 1095 id=3
> LOGIN tty6 2012-06-16 12:57 1097 id=6
> LOGIN tty1 2012-06-16 12:57 1317 id=1
> This is not helpful, as you might guess.
This is *one* of the issues with 'who' -- actually, with utmp/wtmp
handling and usage. 'who' just reports on what it finds in utmp.
LightDM is not writing it, and some of the terminal clients also do not
write it. In fact, *most* of the graphical programs do not interface
with utmp. I have not looked at the other DMs, so YMMV.
> 2) Worse, write does not seem to work at all. If I write to myself, I
> get a message that I'm not logged in.
Yes. 'write' reads utmp to find the user. Since there are no real
records written to it, it fails.
> What am I missing?
(1) the fix in , but this will not completely solve the issue;
(2) a real replacement for utmp, now geared for graphical environments.
utmp, 'who', and 'write' were written a long time ago, when the *IXes
available we mostly command-line. This is not the norm anymore (except
for the server arena). I know of no real replacement as of a few years
ago, when I last searched for it.