On 23.09.17 10:15, Arnt Karlsen wrote:
> ..I still miss and prefer the S.u.S.E.-5.2 way, root had a
> nice red background color in xterms, fairly hard to miss.

If the '#' and "root@hostname" escape the attention of a person
entrusted with root privileges, then why not make the root prompt bright red:

root@ratatosk:/home/erik# export PS1="\[\033[1;31m\]\u@\h:\W\$ \[\033[0;0m\]"

OK, that reverted the '#' to '$', presumably because I'd su-ed, rather
than logged in as root. (\$ => '#' for uid==0, else '$')

As all my xterms are yellow on darkslategrey, one bright red prompt
cannot be missed, even from the other side of the room.

Erik