odt file instant open

odt file instant open

[Olwe Melwasul]

I'm trying to grok the open document format, so I took the first wild
and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
opened up to a "Zip-Archive Narrow" view of all the files contained
therein Poking around on the Internet, I found that Emacs
automatically unpacks a .odt file, which is nothing more than a zip
file. My question is this: How is Emacs doing this? What code is
running (what .el is invoked) to make this happen? Also, where might
documentation be on how to control this zip/unzip functionality with
elisp. I don't want to do a system call, i.e., reinvent the wheel.

O

Re: odt file instant open

[Andreas Röhler]

Am 26.07.2010 18:29, schrieb Olwe Melwasul:
> I'm trying to grok the open document format, so I took the first wild
> and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
> opened up to a "Zip-Archive Narrow" view of all the files contained
> therein Poking around on the Internet, I found that Emacs
> automatically unpacks a .odt file, which is nothing more than a zip
> file. My question is this: How is Emacs doing this?

by calling a shell-command resp. to the ending found.
Exists a list with endings --.zip, .tgz, .gz etc.-- and programs to run for.
Have a look at dired-do-compress for the details.

  What code is
> running (what .el is invoked)

probably dired-find-file

HTH


Andreas

--
https://code.launchpad.net/~a-roehler/python-mode
https://code.launchpad.net/s-x-emacs-werkstatt/

  to make this happen? Also, where might
> documentation be on how to control this zip/unzip functionality with
> elisp. I don't want to do a system call, i.e., reinvent the wheel.
>
> O
>
>

Re: odt file instant open

[Thien-Thi Nguyen]

See also variable ‘auto-mode-alist’.

Re: odt file instant open

[Eli Zaretskii]

> Date: Tue, 27 Jul 2010 09:30:32 +0200
> From: Andreas Röhler <andreas.roehler@easy-emacs.de>
> 
> Am 26.07.2010 18:29, schrieb Olwe Melwasul:
> > I'm trying to grok the open document format, so I took the first wild
> > and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
> > opened up to a "Zip-Archive Narrow" view of all the files contained
> > therein Poking around on the Internet, I found that Emacs
> > automatically unpacks a .odt file, which is nothing more than a zip
> > file. My question is this: How is Emacs doing this?
> 
> by calling a shell-command resp. to the ending found.

No.  For most archive types, arc-mode.el (and tar-mode.el) can list
the contents directly, just by reading the archive file itself.
Extracting the individual files in the archive sometimes needs to run
an external program.

Re: odt file instant open

[Andreas Röhler]

Am 27.07.2010 18:58, schrieb Eli Zaretskii:
>> Date: Tue, 27 Jul 2010 09:30:32 +0200
>> From: Andreas Röhler<andreas.roehler@easy-emacs.de>
>>
>> Am 26.07.2010 18:29, schrieb Olwe Melwasul:
>>> I'm trying to grok the open document format, so I took the first wild
>>> and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
>>> opened up to a "Zip-Archive Narrow" view of all the files contained
>>> therein Poking around on the Internet, I found that Emacs
>>> automatically unpacks a .odt file, which is nothing more than a zip
>>> file. My question is this: How is Emacs doing this?
>>
>> by calling a shell-command resp. to the ending found.
>
> No.  For most archive types, arc-mode.el (and tar-mode.el) can list
> the contents directly, just by reading the archive file itself.
> Extracting the individual files in the archive sometimes needs to run
> an external program.
>
>
>

Hi,

think you mistook the question.
As the OP wrote, he just opened the file without any precaution. The 
surprise was: it worked.

Ignoring so for how opening was done in detail --via find-file or from 
dired probably-- arc-mode seems not involved, but auto-compression-mode 
from jka-cmpr-hook.el etc.

BTW arc-mode too recurs to shell-commands AFAIS,
	  (apply 'call-process
in archive-*-extract for example

Andreas

Re: odt file instant open

[Kevin Rodgers]

Andreas Röhler wrote:
> Am 27.07.2010 18:58, schrieb Eli Zaretskii:
>>> Date: Tue, 27 Jul 2010 09:30:32 +0200
>>> From: Andreas Röhler<andreas.roehler@easy-emacs.de>
>>>
>>> Am 26.07.2010 18:29, schrieb Olwe Melwasul:
>>>> I'm trying to grok the open document format, so I took the first wild
>>>> and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
>>>> opened up to a "Zip-Archive Narrow" view of all the files contained
>>>> therein Poking around on the Internet, I found that Emacs
>>>> automatically unpacks a .odt file, which is nothing more than a zip
>>>> file. My question is this: How is Emacs doing this?
>>>
>>> by calling a shell-command resp. to the ending found.
>>
>> No.  For most archive types, arc-mode.el (and tar-mode.el) can list
>> the contents directly, just by reading the archive file itself.
>> Extracting the individual files in the archive sometimes needs to run
>> an external program.
> 
> Hi,
> 
> think you mistook the question.
> As the OP wrote, he just opened the file without any precaution. The 
> surprise was: it worked.
> 
> Ignoring so for how opening was done in detail --via find-file or from 
> dired probably--

I think you misread the question, that is exactly what the OP asked about:

How is Emacs doing this? What code is
running (what .el is invoked) to make this happen?

> arc-mode seems not involved, but auto-compression-mode 
> from jka-cmpr-hook.el etc.

This entry from auto-mode-alist suggests otherwise:

  ("\\.\\(sx[dmicw]\\|od[fgpst]\\|oxt\\)\\'" . archive-mode)

> BTW arc-mode too recurs to shell-commands AFAIS,
>       (apply 'call-process
> in archive-*-extract for example

Good point, which Eli made above as well.  Here's what arc-mode.el says:

;; This code does not decode any files internally, although it does
;; understand the directory level of the archives.

-- 
Kevin Rodgers
Denver, Colorado, USA

Re: odt file instant open

[Andreas Röhler]

Am 28.07.2010 15:10, schrieb Kevin Rodgers:
> Andreas Röhler wrote:
>> Am 27.07.2010 18:58, schrieb Eli Zaretskii:
>>>> Date: Tue, 27 Jul 2010 09:30:32 +0200
>>>> From: Andreas Röhler<andreas.roehler@easy-emacs.de>
>>>>
>>>> Am 26.07.2010 18:29, schrieb Olwe Melwasul:
>>>>> I'm trying to grok the open document format, so I took the first wild
>>>>> and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
>>>>> opened up to a "Zip-Archive Narrow" view of all the files contained
>>>>> therein Poking around on the Internet, I found that Emacs
>>>>> automatically unpacks a .odt file, which is nothing more than a zip
>>>>> file. My question is this: How is Emacs doing this?
>>>>
>>>> by calling a shell-command resp. to the ending found.
>>>
>>> No. For most archive types, arc-mode.el (and tar-mode.el) can list
>>> the contents directly, just by reading the archive file itself.
>>> Extracting the individual files in the archive sometimes needs to run
>>> an external program.
>>
>> Hi,
>>
>> think you mistook the question.
>> As the OP wrote, he just opened the file without any precaution. The
>> surprise was: it worked.
>>
>> Ignoring so for how opening was done in detail --via find-file or from
>> dired probably--
>
> I think you misread the question, that is exactly what the OP asked about:
>
> How is Emacs doing this? What code is
> running (what .el is invoked) to make this happen?
>
>> arc-mode seems not involved, but auto-compression-mode from
>> jka-cmpr-hook.el etc.
>
> This entry from auto-mode-alist suggests otherwise:
>
> ("\\.\\(sx[dmicw]\\|od[fgpst]\\|oxt\\)\\'" . archive-mode)
>

You are right here, Eli too. So the mistake is mine in this point.
.odt is handled differently from other archives as


  ("\\.g?z\\(~\\|\\.~[0-9]+~\\)?\\'" nil jka-compr)
  ("\\.bz2\\(~\\|\\.~[0-9]+~\\)?\\'" nil jka-compr)
  ("\\.Z\\(~\\|\\.~[0-9]+~\\)?\\'" nil jka-compr)

where I poked around some weeks ago...

Thanks

Andreas



>> BTW arc-mode too recurs to shell-commands AFAIS,
>> (apply 'call-process
>> in archive-*-extract for example
>
> Good point, which Eli made above as well. Here's what arc-mode.el says:
>
> ;; This code does not decode any files internally, although it does
> ;; understand the directory level of the archives.
>

Re: odt file instant open

[Stefan Monnier]

> You are right here, Eli too. So the mistake is mine in this point.
> .odt is handled differently from other archives as

>  ("\\.g?z\\(~\\|\\.~[0-9]+~\\)?\\'" nil jka-compr)
>  ("\\.bz2\\(~\\|\\.~[0-9]+~\\)?\\'" nil jka-compr)
>  ("\\.Z\\(~\\|\\.~[0-9]+~\\)?\\'" nil jka-compr)

Because these are not archives, but compressed files (they contain only
a single file, whereas archives typically contain several files).
Of course many .gz files have as their single "contained" file an
archive (or format Tar) which itself contains several file.


        Stefan

Re: odt file instant open

[Stefan Monnier]

> Ignoring so for how opening was done in detail --via find-file or from dired
> probably-- arc-mode seems not involved, but auto-compression-mode from
> jka-cmpr-hook.el etc.

No: jka-compr is only used for compression-only format, like gzip,
compress, bzip, lzma, ... for archives of files (compressed or not),
it's either tar-mode (used for tarballs) or arc-mode (used for ar, zip,
lha, zoo, ...).

> BTW arc-mode too recurs to shell-commands AFAIS,
> 	  (apply 'call-process
> in archive-*-extract for example

Yes, that's what Eli said:

   Extracting the individual files in the archive sometimes needs to run
   tan external program.


-- Stefan

Re: odt file instant open

[Eli Zaretskii]

> Date: Mon, 26 Jul 2010 11:29:17 -0500
> From: Olwe Melwasul <hercynianforest@gmail.com>
> 
> My question is this: How is Emacs doing this? What code is
> running (what .el is invoked) to make this happen?

arc-mode.el

> Also, where might documentation be on how to control this zip/unzip
> functionality with elisp.

Read the code and comments of arc-mode.el.

Re: odt file instant open

[Jason White]

Olwe Melwasul <hercynianforest@gmail.com> writes:

> I'm trying to grok the open document format, so I took the first wild
> and crazy step of simply trying to open it in Emacs (23.2.1) -- and it
> opened up to a "Zip-Archive Narrow" view of all the files contained
> therein 

The following may be useful:
http://www.cb1.com/~john/computing/emacs/lisp/editing/odf-mode.el