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Date: Mon, 07 Jul 2014 18:00:38 +0100
From: Arthur Chance <freebsd@qeng-ho.org>
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To: Ralf Mardorf <ralf.mardorf@rocketmail.com>, freebsd-questions@freebsd.org
Subject: Re: [Bulk] Re: The name "grep"
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On 07/07/2014 17:28, Ralf Mardorf wrote:
>
>> On Mon, 07 Jul 2014 14:21:04 +0100, Arthur Chance wrote:
>>> 	dd [options] [ infile [ outfile ]]
>
> This way users by accident could mistake the infile with the outfile.
>
> We dislike to randomly screw up infile and outfile, so IMO it makes
> sense to force if= and of= "operands".

There's no problem about which file is input and which output with cp or 
mv, so why on earth would it be a problem with a sane version of dd?

If you really need a hand holding indication of which file is which,

	dd -i $infile -o $outfile

would be in the Unix spirit, unlike the existing form. And with an 
interactive shell you could use filename completion which fails with the 
existing dd.