Subject: Re: bug#22084: Potential Bug in sort -r

From: Adria Rovira <[email-masked]>
Date: Thu, 3 Dec 2015 18:28:43 +0100

Dear Assaf,

Thank You very much!!

We didn't read carefully enough the manual.

Best Regards,

Adrià

On 12/03/2015 06:18 PM, Assaf Gordon wrote:
> tag 22084 notabug
> close 22084
> stop
>
> Hello Adrià and Deimos,
>
>
> On 12/03/2015 07:30 AM, Adrià Rovira wrote:
>> I noticed the reverse option is not correctly applied if it has to 
>> sort by more than one column.
>
> This is not a bug, but simply a usage issue.
> The "sort --help" page states:
> " ... OPTS is one or more single-letter ordering options [bdfgiMhnRrV],
> which override global ordering options for that key. "
>
> That is,
> 1. If you use global sorting option (-n), and a key option WITHOUT
>    ordering option (e.g. '-k1,1') - the global sorting option is in 
> effect.
>
> 2. If you use *any* sorting option in the key specification
>  (e.g. '-k1,1r'), it overrides the global sorting option,
>  thus the order in effect is just 'reverse' (implying: alphabetical 
> order).
>
> These examples should demonstrate it:
>
>     # Input data
>     $ printf "1\n07\n2\n"
>     1
>     07
>     2
>         # Alphabetical (ascii) sort,
>     # character "0" comes before "1"
>     $ printf "1\n07\n2\n" | sort
>     07
>     1
>     2
>         # Numerical sort, value 7 comes after 2
>     $ printf "1\n07\n2\n" | sort -n
>     1
>     2
>     07
>         # Global option (-n), key without ordering option:
>     # numeric sort in effect
>     $ printf "1\n07\n2\n" | sort -n -k1,1
>     1
>     2
>     07
>         # Global option (-n), key with any ordering option
>     # (in this case 'b' = ignore leading blanks)
>     # global numeric ordering is ignore
>     $ printf "1\n07\n2\n" | sort -n -k1b,1
>     07
>     1
>     2
>         # Adding the numeric ordering to the key -
>     # takes effect
>     $ printf "1\n07\n2\n" | sort -n -k1bn,1
>     1
>     2
>     07
>
>
> regards,
>  - Assaf
>
>

-- 
--------------------------------------------------------
o o o | Adrià Rovira Garcia
o o o | Research group of Astronomy and GEomatics (gAGE)
o o o | Universitat Politècnica de Catalunya (UPC)
--------------------------------------------------------

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