> I'm not observing this problem in coreutils 8.29, the current version. [...]
It took me a while to reproduce the problem. It seems, I startet with $ echo " 1 1 1 1 2 3 1 1 4 2 4 4 " | uniq -c f2 trying to sort some values. Then I went "up" in the history and deleted the unneeded newlines (also changing the sort-field value, so suddenly the output was the one I submited as bug. Then I tried to sort some letters, and the bug did not appear. So I thougt, it might have to do with letters and numbers - and of cause with the field-value in sort. Actually this was / is the problem: ## tl;dr ## $ echo -e "a""\n""a" | uniq # I use doublequotes to distinguish the characters a $ echo -e "a""\n""a"" " | uniq # I think this one happened to me; could not see it in i/o $ echo -e "a""\n""\r""a" | uniq a a # note: the control character could be before / after one of the values # it works same way with "\a" and "\b" So it is not an unexpected behaviour of uniq -f, but of uniq / sort -u.
