[PATCH, resend] document sort --ignore-case --unique interaction

[jidanni]

Signed-off-by: jidanni <address@hidden>
---
No reply last time so resending.

 doc/coreutils.texi |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/doc/coreutils.texi b/doc/coreutils.texi
index d8df107..06b259c 100644
--- a/doc/coreutils.texi
+++ b/doc/coreutils.texi
@@ -3742,6 +3742,10 @@ is a space or a tab, but the @env{LC_CTYPE} locale can 
change this.
 Fold lowercase characters into the equivalent uppercase characters when
 comparing so that, for example, @samp{b} and @samp{B} sort as equal.
 The @env{LC_CTYPE} locale determines character types.
+When used with @option{--unique} those lower case equivalent lines are
+thrown away. (There is currently no way to throw away the upper case
+equivalent instead. (Any @option{--reverse} given would only affect
+the final result, after the throwing away.))
 
 @item -g
 @itemx --general-numeric-sort
-- 
1.6.0.6