Comparing two lists [SOLVED (at least it looks like that)]

[b. f.]

> 2011-05-07 02:09, Rolf Nielsen skrev:
> > Hello all,
> >
> > I have two text files, quite extensive ones. They have some lines in
> > common and some lines are unique to one of the files. The lines that do
> > exist in both files are not necessarily in the same location. Now I need
> > to compare the files and output a list of lines that exist in both
> > files. Is there a simple way to do this? diff? awk? sed? cmp? Or a
> > combination of two or more of them?
...
> sort file1 file2 | uniq -d

If the lines aren't repeated in only one file...

For future reference, comm(1) exists to handle problems like this,
although (of course) TIMTOWTDI.

b.