Subject: Mention more about uniq failure exit status

From: 積丹尼 Dan Jacobson <[email-masked]>
Date: Wed, 08 Jan 2020 01:02:47 +0800

(info "(coreutils) uniq invocation") says
   An exit status of zero indicates success, and a nonzero value
   indicates failure.

The user wonders:
"Failure to make a file unique because it was already unique?"
Be more explicit.