Is it possible to decide what is a gpg file?

[Mario Castelán Castro]

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November 17th for David SMITH <dave.smith at st.com>

Linux do not have a file command, that belogs to the rest of the OS.

Linux is only a kernel than is commonly used with the GNU Operating
System, but the name for that system is GNU or GNU/Linux.

In advance thanks by your understanding.
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7YUAnA88xhLNkHO/LsTXLBWsR6Ed9+s2
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2009/11/17 David SMITH <dave.smith at st.com>:
> On Tue, Nov 17, 2009 at 10:52:29AM -0500, Melikamp The Medley wrote:
>> Sorry if you get two of these, I screwed up while subscribing
>> to the list.
>>
>> I have a question relating to the symmetric encryption. If I do
>>
>> gpg -c foo-file
>>
>> and enter a passphrase, I get an encrypted foo-file.gpg.
>> Is there a way to tell that it is an encrypted file just by
>> looking at the contents? I mean, is there a reliable way to
>> tell that something is _not_ an encrypted file?
>
> Depends on what you mean by "reliable"...
>
> I'm sure if you read RFC-4880, you could work out a byte pattern that
> would give a very good indication, for most practical purposes.
>
> However, it would probably be possible for someone to generate a file
> artificially in a deliberate attempt to fool the filetype detection
> mechanism.  So, it's not "reliable" because it can be fooled
> intentionally, but for most likely scenarii (i.e. where people aren't
> deliberately trying to fool it), it would work.
>
> If you're running on UNIX (particularly Linux), look at 'man file'.