doc: clarify the operation of uniq -uD

The description of -u was inaccurate when combined with -D:

  $ printf '%s\n' '1 a' '2 a' | uniq -uD -f1
  1 a

* doc/coreutils.texi (uniq invocation): Clarify that it's
the last repeated line that is suppressed from the output.

Fixes http://bugs.gnu.org/17022

diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index e5e27eb88e930a29a28e4952ece288f190244f4c..75875d88c41f49ba7760e87df7873f6683040e40 100644 (file)
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -5210,8 +5210,9 @@ This is a GNU extension.
 @opindex -u
 @opindex --unique
 @cindex unique lines, outputting
-Discard the first repeated line.  When used by itself, this option
-causes @command{uniq} to print unique lines, and nothing else.
+Discard the last line that would be output for a repeated input group.
+When used by itself, this option causes @command{uniq} to print unique
+lines, and nothing else.
 
 @item -w @var{n}
 @itemx --check-chars=@var{n}