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From: Milan Broz <gmazyland@gmail.com>
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Date: Wed, 23 Sep 2015 10:39:06 +0200
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Subject: Re: [dm-crypt] How to recognize a LUKS container
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To: =?UTF-8?Q?Michael_Kj=c3=b6rling?= <michael@kjorling.se>, dm-crypt@saout.de

On 09/23/2015 09:50 AM, Michael Kjörling wrote:
> On 23 Sep 2015 02:29 +0000, from hmccurdy@yahoo.com (H McCurdy):
>> I might have figured it out but can't test my idea until tomorrow. 
>> My thought is to try to access it as if it exists and if the
>> function returns -1, then it's not a valid LUKS container.  Anyway,
>> that's my idea.
> 
> For the scenario you describe, something like
> 
> # test -r $DEVICE && cryptsetup isLuks $DEVICE && echo It is LUKS

In generoic scripts I would better suggest to use blkid
(or libblkid if you need link to a library).

See blkid man page for all formatting etc. parameters.

Milan