When I launch wireshark(from k-menu..run, or from the command line) it loads but doesn't list interfaces unless I do sudo wireshark or I suppose if I do su then wireshark. That's fine.
But sudo wireshark or su<ENTER>wireshark<ENTER> isn't working.

It worked yesterday but now when I try, I get this error






knoppix@Microknoppix:~$ su root
root@Microknoppix:/home/knoppix# wireshark
No protocol specified

(wireshark:4986): Gtk-WARNING **: cannot open display: :0
root@Microknoppix:/home/knoppix# su knoppix
knoppix@Microknoppix:~$ sudo wireshark
No protocol specified

(wireshark:503: Gtk-WARNING **: cannot open display: :0
knoppix@Microknoppix:~$