Subject: Re: bug#76290: "sort -u" vs "sort -h -u": possible bug

From: Paul Eggert <[email-masked]>
Date: Wed, 19 Feb 2025 13:21:14 -0800

On 2/19/25 11:15, Rainer Canavan wrote:
> -u, --unique
>               with -c, check for strict ordering; without -c, output 
> only the first of an equal run
> 
> does not provide any explanation what 'equal' or 'run' may mean. Maybe 
> add something like "where equality is assessed only based on the keys 
> and rules used to sort the output".

Thanks for the suggestion. Although that's a bit long for "sort --help", 
I take the point that equality comparison could be mentioned and 
installed the attached to try to make things clearer without adding so 
much length.

From 3324344820b6f3566ed659befe9bbfcf2b1f1298 Mon Sep 17 00:00:00 2001
From: Paul Eggert <[email-masked]>
Date: Wed, 19 Feb 2025 13:17:48 -0800
Subject: [PATCH] sort: improve -u brief doc

* src/sort.c (usage): Reword -u help (Bug#76290).
---
 src/sort.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/sort.c b/src/sort.c
index 4473987ef..b10183b6f 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -498,9 +498,8 @@ Other options:\n\
   -T, --temporary-directory=DIR  use DIR for temporaries, not $TMPDIR or %s;\n\
                               multiple options specify multiple directories\n\
       --parallel=N          change the number of sorts run concurrently to N\n\
-  -u, --unique              with -c, check for strict ordering;\n\
-                              without -c, output only the first of an equal run\
-\n\
+  -u, --unique              output only the first of lines with equal keys;\n\
+                              with -c, check for strict ordering\n\
 "), DEFAULT_TMPDIR);
       fputs (_("\
   -z, --zero-terminated     line delimiter is NUL, not newline\n\
-- 
2.48.1