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September 18, 2010
Re: [OT] File type on UNIX
On Sep 18, 10 04:24, "Jérôme M. Berger" wrote:
> KennyTM~ wrote:
>> On Sep 17, 10 02:26, "Jérôme M. Berger" wrote:
[-snip-]
>>
>> This describes the file(1) command, which the job is to inspect the file
>> content and conclude what kind of file it actually is.
>>
> 	I suggest you re-read the paragraph I posted. Although it was taken
> from the "file" web site, it states clearly that other apps look at
> the file contents instead of the extension. Of course, some apps
> don't care about the file type but some do. And most of those that
> do care don't use the extension.
>

Many apps in Windows doesn't care about the file extension too. You can 
rename a bitmap to 'file.txt' and still can open it in MS Paint. This is 
irrelevant to UNIX.

>> But this is just one particular UNIX command. The command line interface
>> in general does not care about the type of a regular file. This is
>> needed in the GUI, but it is outside of the common parts of UNIX. There
>> is no rule saying that a file manager must use file(1) or MIME type or
>> extensions to determine the file type.
>>
> 	True, but then, there is no rule that says that on windows a file
> manager must use the extension. However, on Windows, all the file
> managers I've tried have used the extension (actually, most of the
> time they don't use the extension themselves, they simply ask
> Windows to open the file and Windows uses the extension), whereas on
> UNIX most file managers use the file contents (usually, they don't
> use the file command, but instead rely on libmagic directly) and
> most applications will ignore the extension when asked to open a
> file (OK, some Windows applications do that too but on *NIX most of
> them do).
>
> 		Jerome

Mac OS X is UNIX. Finder cares about the file extension (besides metadata).
September 20, 2010
Re: [OT] File type on UNIX
KennyTM~ wrote:
>>     True, but then, there is no rule that says that on windows a file
>> manager must use the extension. However, on Windows, all the file
>> managers I've tried have used the extension (actually, most of the
>> time they don't use the extension themselves, they simply ask
>> Windows to open the file and Windows uses the extension), whereas on
>> UNIX most file managers use the file contents (usually, they don't
>> use the file command, but instead rely on libmagic directly) and
>> most applications will ignore the extension when asked to open a
>> file (OK, some Windows applications do that too but on *NIX most of
>> them do).
>>
>>         Jerome
> 
> Mac OS X is UNIX. Finder cares about the file extension (besides metadata).

most: You can use *most* to refer to the majority of a group of
things or people or the largest part of something.

One counter example does not invalidate my point. Especially when
the example is invalid: MacOS X is *not* UNIX. True, the low level
parts are UNIX-based, which makes it easy to port UNIX apps, however
that doesn't make the whole into a UNIX. In particular, finder was
ported from older versions of MacOS and inherits a large part of its
behaviour from those older versions.

		Jerome
-- 
mailto:jeberger@free.fr
http://jeberger.free.fr
Jabber: jeberger@jabber.fr
September 20, 2010
Re: [OT] File type on UNIX
On Sep 21, 10 00:04, "Jérôme M. Berger" wrote:
> KennyTM~ wrote:
>>>      True, but then, there is no rule that says that on windows a file
>>> manager must use the extension. However, on Windows, all the file
>>> managers I've tried have used the extension (actually, most of the
>>> time they don't use the extension themselves, they simply ask
>>> Windows to open the file and Windows uses the extension), whereas on
>>> UNIX most file managers use the file contents (usually, they don't
>>> use the file command, but instead rely on libmagic directly) and
>>> most applications will ignore the extension when asked to open a
>>> file (OK, some Windows applications do that too but on *NIX most of
>>> them do).
>>>
>>>          Jerome
>>
>> Mac OS X is UNIX. Finder cares about the file extension (besides metadata).
>
> most: You can use *most* to refer to the majority of a group of
> things or people or the largest part of something.
>
> One counter example does not invalidate my point. Especially when
> the example is invalid: MacOS X is *not* UNIX. True, the low level
> parts are UNIX-based, which makes it easy to port UNIX apps, however
> that doesn't make the whole into a UNIX. In particular, finder was
> ported from older versions of MacOS and inherits a large part of its
> behaviour from those older versions.
>
> 		Jerome

Your definition of Unix is wrong then. Unix *only* specifies the API 
(system interface and headers) and the command-line utilities. You *are* 
confusing Unix and the distro.

Ref: http://www.opengroup.org/onlinepubs/9699919799/
September 20, 2010
Re: [OT] File type on UNIX
KennyTM~ wrote:
> Your definition of Unix is wrong then. Unix *only* specifies the API
> (system interface and headers) and the command-line utilities. You *are*
> confusing Unix and the distro.
> 
> Ref: http://www.opengroup.org/onlinepubs/9699919799/

	That's not UNIX, that's POSIX! And by that definition, Windows
would be UNIX too...

		Jerome
-- 
mailto:jeberger@free.fr
http://jeberger.free.fr
Jabber: jeberger@jabber.fr
September 20, 2010
Re: [OT] File type on UNIX
On Monday, September 20, 2010 10:43:36 Jérôme M. Berger wrote:
> KennyTM~ wrote:
> > Your definition of Unix is wrong then. Unix *only* specifies the API
> > (system interface and headers) and the command-line utilities. You *are*
> > confusing Unix and the distro.
> > 
> > Ref: http://www.opengroup.org/onlinepubs/9699919799/
> 
> 	That's not UNIX, that's POSIX! And by that definition, Windows
> would be UNIX too...
> 
> 		Jerome

Actually, technically, for an OS to be unix, it not only has to follow the 
appropriate specification, but someone has to foot the bill for it be certified. 
So, most OSes which are essentially unix aren't technically unix - Linux being a 
prime example. Personally, I think that it's a bit silly, but that's the way it 
is (since Unix is trademarked).  Posix is a separate - albeit related - spec.

Most of the stuff which cares about file extensions or mime types is going to be 
GUI-related and that has pretty much nothing to do with either unix or posix. 
However, it is typical for Linux systems (and I assume BSD systems) to use the 
mime type primarily rather than the file extension. I had thought that Mac OS X 
was the same in that regard, but I guess not. I don't know though, since I don't 
use it.

- Jonathan M Davis
September 20, 2010
Re: [OT] File type on UNIX
On Sep 21, 10 01:43, "Jérôme M. Berger" wrote:
> KennyTM~ wrote:
>> Your definition of Unix is wrong then. Unix *only* specifies the API
>> (system interface and headers) and the command-line utilities. You *are*
>> confusing Unix and the distro.
>>
>> Ref: http://www.opengroup.org/onlinepubs/9699919799/
>
> 	That's not UNIX, that's POSIX! And by that definition, Windows
> would be UNIX too...
>
> 		Jerome

Looks like we have no point keep discussing on this since we have 
different view on what Unix means.

My points are just:
 - in the CLI the type of regular file is usually irrelevant.
 - Unix (i.e. POSIX) doesn't specify how should the desktop component 
of the operating system determine the type of a regular file. Free 
desktop environments (e.g. Gnome, KDE, XFCE) stores the file type as 
MIME type.
September 20, 2010
Re: [OT] File type on UNIX
Tue, 21 Sep 2010 02:40:18 +0800, KennyTM~ wrote:

> On Sep 21, 10 01:43, "Jérôme M. Berger" wrote:
>> KennyTM~ wrote:
>>> Your definition of Unix is wrong then. Unix *only* specifies the API
>>> (system interface and headers) and the command-line utilities. You
>>> *are* confusing Unix and the distro.
>>>
>>> Ref: http://www.opengroup.org/onlinepubs/9699919799/
>>
>> 	That's not UNIX, that's POSIX! And by that definition, Windows
>> would be UNIX too...
>>
>> 		Jerome
> 
> Looks like we have no point keep discussing on this since we have
> different view on what Unix means.
> 
> My points are just:
>   - in the CLI the type of regular file is usually irrelevant. - Unix
>   (i.e. POSIX) doesn't specify how should the desktop component
> of the operating system determine the type of a regular file. Free
> desktop environments (e.g. Gnome, KDE, XFCE) stores the file type as
> MIME type.

The post by Jonathan M Davis ( http://www.digitalmars.com/webnews/
newsgroups.php?art_group=digitalmars.D&article_id=117660 ) was the most 
informative post in this thread. You should both study that carefully.
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