filemananger for emacs with meta information about a file without opening it

filemananger for emacs with meta information about a file without opening it

[Uwe Brauer]

Hi 

I am looking for a kind of «filemanager» for emacs, that allows me to
obtain some meta information (about the content of the file) without
opening it. 

I am aware of org-note etc, but this type of information is only
revealed if one opens the file. 

So https://github.com/DerBeutlin/filetags.el allows me to add
information in form of tags to the file name.

However does anybody know any other tools with a similar functionality?

Regards

Uwe Brauer 

-- 
Warning: Content may be disturbing to some audiences
I strongly condemn Putin's war of aggression against the Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the ban of Russia from SWIFT.
I support the EU membership of the Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

Re: filemananger for emacs with meta information about a file without opening it

[Michael Heerdegen]

Uwe Brauer <oub@mat.ucm.es> writes:

> Hi 
>
> I am looking for a kind of «filemanager» for emacs, that allows me to
> obtain some meta information (about the content of the file) without
> opening it. 
>
> I am aware of org-note etc, but this type of information is only
> revealed if one opens the file. 

I didn't understand whether you would want to be able to add arbitrary
information about a file to some sort of database.  Or only want to see
information about the file type or image dimensions or such things.

Michael.

Re: filemananger for emacs with meta information about a file without opening it

[Jean Louis]

* Uwe Brauer <oub@mat.ucm.es> [2022-10-31 23:50]:
> I am looking for a kind of «filemanager» for emacs, that allows me to
> obtain some meta information (about the content of the file) without
> opening it. 

In Dired, one uses `y' to get basic information about the file without
opening it. Often I use it for pictures to find out the resolution.

> So https://github.com/DerBeutlin/filetags.el allows me to add
> information in form of tags to the file name.
> 
> However does anybody know any other tools with a similar
> functionality?

In my production I use Hyperscope for GNU Emacs, which is not
something I can easily provide for people in public to install it as I
have not prepared yet the public version, but I can guide user
individually to install it.

Reference:

About Dynamic Knowledge Repositories (DKR):
https://www.dougengelbart.org/content/view/190/163/

Of course I use tags, all kinds of tags, and pretty freely. The name
of file in my system is less important, I do not even remember file
names. I search by semantics mostly.

Elementary Objects:
https://www.dougengelbart.org/content/view/110/460/#2a1a

Elementary objects can be anything and defined by user. Thus I can
make a simple letter A to be elementary object of type "Letter". This
way it becomes possible to finely reference the letter A within the
word, to describe the letter "A", tag it anyhow, and provide other
meta information.

Major count of tags I use:

┌─────────────────────────────┬────────┐
│         Description         │ Count  │
├─────────────────────────────┼────────┤
│ Total tags: Hyperdocuments  │ 124808 │
│ Total tags: People          │   2354 │
│ Total number of unique tags │   1689 │
└─────────────────────────────┴────────┘

System uses currently tabulated-list-mode, but it could be re-worked
to user hierarchy or other way of display and presentation. Its
selection and searches may be exported to operating system, Emacs need
not be the only way to access it.

Let us say I have Gnumeric spreadsheet, I may see in the list only
following:

64763 Density Calculation      Gnumeric, Spreadsheet

Tags could be: TAGS:  spreadsheet gnumeric density 

and the location of file is totally of no interest to me, but I can
see it in the system to be:
"/home/data1/protected/hyperscope/6/4/7/6/2/2022/02/2022-02-12/Density.gnumeric"

However, I never look for file by using the file system. Hyperscope
uses logic and files the file in right place, me I am using only
semantics, tags, or other attributes to get to the file.

Meta data is thus something that I generate myself. Files are "filed"
into system, that is analogous to Org capturing. Buffer, region, file
may be captured into the system, defined, described, tagged, sorted,
classified, and then it is forgotten. 

and meta data could be:

                             ID   64763
                   Date created   "2022-02-12 17:52:33.183056+03"
                  Date modified   "2022-11-03 09:41:53.959006+03"
                   User created   "maddox"
                  User modified   "maddox"
                  Search Status   "Default"
            Start Date and Time   nil
              End Date and Time   nil
                    Markup Type   "Default (Text)"
                      Note Type   "Gnumeric"
                       Sub-type   "Spreadsheet"
                           Name   "Density Calculation"
                      Hyperlink   "/home/data1/protected/hyperscope/6/4/7/6/2/2022/02/2022-02-12/Density.gnumeric"
                      Arguments   nil
                    Description   ""
                           Text   nil
           Internal information   nil
                      Parent ID   "Spreadsheets for mining/prospecting purposes"
                         Author   nil
                     Permission   "Default"
                       Revision   nil
                Number of pages   nil
                       Language   nil
                      File size   nil
                    Time length   nil
                          Width   nil
                         Height   nil
                           Hash   "6a7b327b081d5ae722fe457b0aee876a7c33b7bbcdd10799eee0cd5bb7f448861fedc823de69f0b0296153510e4c508e848c9a1c1576ad7abcc4532885a28bcc"
                  GPG Signature   nil
                          Pages   nil
            Related people list   nil
                 Related person   nil
               Related business   nil
                  Search status   1
                   Set Priority   100
                    Author Name   nil
                     Properties   nil
                Emacs Lisp Hash   nil
                      Publisher   nil
 AVAILABLE (was Related to group)   nil
        Assigned to people list   nil
            Assigned to contact   nil
                    Global Rank   6
                         Active   t
                  Action status   ""
                Global priority   100000
                   Related URIs   nil
                       Template   nil
                       WRS Area   nil
                Publishing type   nil
                           Slug   nil
                        License   nil
                      File type   ".html HTML File"
                         Report   nil
                         Tokens   "'/home/data1/protected/hyperscope/6/4/7/6/2/2022/02/2022-02-12/density.gnumeric':4 '64763':3 'calcul':2 'densiti':1,7 'gnumer':6 'spreadsheet':5"
             Temporary Document   nil
            Override Major Mode   nil
                    Minor Modes   nil
                Related country   nil
                      Report to   nil
              Physical location   nil
                    Lead Source   nil
                       Currency   nil
               Sales Flow Stage   nil
                   WRS Category   nil
                       WRS Menu   nil
                   WRS Keywords   nil
                   WRS Priority   10
                WRS Not in Menu   nil
                  WRS Main Page   nil
                   WRS OG Image   nil
                        Curator   "Jean Louis"
                      Comm Line   nil
                       Location   nil
 AVAILABLE (was Assigned to people list)   nil
                            SKU   nil
                 Value or Price   nil
                  Introduced by   nil
                           UUID   "30c35eb6-c110-429e-8521-0498a3af0c3b"

Hyperscope for Emacs: Demonstration of Semi-Automatic Hyperlinking:
https://gnu.support/images/2021/05/2021-05-13/2021-05-13-20:01:55.ogv

Screenshot on 2021-05-10 of Hyperscope for Emacs:
https://hyperscope.link/3/7/2/7/3/Screenshot-on-2021-05-10-of-Hyperscope-for-Emacs-37273.html

Sample GNU Hyperbole usage with Hyperscope for Emacs:
https://hyperscope.link/3/7/4/7/0/Sample-GNU-Hyperbole-usage-with-Hyperscope-for-Emacs-37470.html

That is type of a "file manager" however, it does not relate to file
system, but to Dynamic Knowledge Repository, and files are only types
of elementary objects which can be any information in general.

-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

In support of Richard M. Stallman
https://stallmansupport.org/

Re: filemananger for emacs with meta information about a file without opening it

[tomas]

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On Thu, Nov 03, 2022 at 09:49:17AM +0300, Jean Louis wrote:
> * Uwe Brauer <oub@mat.ucm.es> [2022-10-31 23:50]:
> > I am looking for a kind of «filemanager» for emacs, that allows me to
> > obtain some meta information (about the content of the file) without
> > opening it. 
> 
> In Dired, one uses `y' to get basic information about the file without
> opening it. Often I use it for pictures to find out the resolution.

How do you find out a picture's resolution without opening the file?

Cheers
-- 
t

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Re: filemananger for emacs with meta information about a file without opening it

[Yuri Khan]

On Thu, 3 Nov 2022 at 14:58, <tomas@tuxteam.de> wrote:

> > In Dired, one uses `y' to get basic information about the file without
> > opening it. Often I use it for pictures to find out the resolution.
>
> How do you find out a picture's resolution without opening the file?

Nohow. The opening is just not perceived by the user. The pedantic
description would probably be “without visiting in a buffer and
without starting an associated interactive application”.

Re: filemananger for emacs with meta information about a file without opening it

[tomas]

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On Thu, Nov 03, 2022 at 03:17:18PM +0700, Yuri Khan wrote:
> On Thu, 3 Nov 2022 at 14:58, <tomas@tuxteam.de> wrote:
> 
> > > In Dired, one uses `y' to get basic information about the file without
> > > opening it. Often I use it for pictures to find out the resolution.
> >
> > How do you find out a picture's resolution without opening the file?
> 
> Nohow. The opening is just not perceived by the user. The pedantic
> description would probably be “without visiting in a buffer and
> without starting an associated interactive application”.

Ah. Visiting a buffer was the elephant I was missing in the room :)

Thanks
-- 
t

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Re: filemananger for emacs with meta information about a file without opening it

[Emanuel Berg]

Jean Louis wrote:

>> I am looking for a kind of «filemanager» for emacs, that
>> allows me to obtain some meta information (about the
>> content of the file) without opening it.
>
> In Dired, one uses `y' to get basic information about the
> file without opening it. Often I use it for pictures to find
> out the resolution.

That's file(1) ...

Yes, the _actual_ ten commandments ...

> ┌─────────────────────────────┬────────┐
> │         Description         │ Count  │
> ├─────────────────────────────┼────────┤
> │ Total tags: Hyperdocuments  │ 124808 │
> │ Total tags: People          │   2354 │
> │ Total number of unique tags │   1689 │
> └─────────────────────────────┴────────┘

Pretty ...

-- 
underground experts united
https://dataswamp.org/~incal

Re: filemananger for emacs with meta information about a file without opening it

[Uwe Brauer]

>>> "MH" == Michael Heerdegen <michael_heerdegen@web.de> writes:

> Uwe Brauer <oub@mat.ucm.es> writes:
>> Hi 
>> 
>> I am looking for a kind of «filemanager» for emacs, that allows me to
>> obtain some meta information (about the content of the file) without
>> opening it. 
>> 
>> I am aware of org-note etc, but this type of information is only
>> revealed if one opens the file. 

> I didn't understand whether you would want to be able to add arbitrary
> information about a file to some sort of database.  

This is what I am looking for. More and more I think that filetags is
not the right thing, because most of my important files are under (HG)
version control, change the file name frequently is not a very smart
thing then.

I found https://github.com/gunther-bachmann/emacs-dired-annotator

Which looks very promising, although right now I have difficulties make
it to work (in git master 7bf17ceee8c, may 2022) and opened already some
issues on this github page
If someone is also interested in that package and want to join...

Uwe 



-- 
Warning: Content may be disturbing to some audiences
I strongly condemn Putin's war of aggression against the Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the ban of Russia from SWIFT.
I support the EU membership of the Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

Re: filemananger for emacs with meta information about a file without opening it

[Emanuel Berg]

Uwe Brauer wrote:

> change the file name frequently is not a very smart
> thing then.

It's a smart thing to do once, into something smart.

-- 
underground experts united
https://dataswamp.org/~incal

Re: filemananger for emacs with meta information about a file without opening it

[Michael Heerdegen]

Yuri Khan <yuri.v.khan@gmail.com> writes:

> > How do you find out a picture's resolution without opening the file?
>
> Nohow. The opening is just not perceived by the user. The pedantic
> description would probably be “without visiting in a buffer and
> without starting an associated interactive application”.

I read it as "without reading the complete file contents from disk".

To get some metadata about images one has to look at the contents but
the first N bytes may be enough with an appropriate small N.

Michael.

Re: filemananger for emacs with meta information about a file without opening it

[Uwe Brauer]

>>> "EB" == Emanuel Berg <incal@dataswamp.org> writes:

> Uwe Brauer wrote:
>> change the file name frequently is not a very smart
>> thing then.

> It's a smart thing to do once, into something smart.

Well if you have 100 commits but have changed every 10th commit the file
name, good luck with annotate.


-- 
Warning: Content may be disturbing to some audiences
I strongly condemn Putin's war of aggression against the Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the ban of Russia from SWIFT.
I support the EU membership of the Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

Re: filemananger for emacs with meta information about a file without opening it

[Emanuel Berg]

Uwe Brauer wrote:

>> It's a smart thing to do once, into something smart.
>
> Well if you have 100 commits but have changed every 10th
> commit the file name, good luck with annotate.

Indeed, do it enough and often enough it doesn't have to
be good.

Quantity has its own quality, as Comrade Stalin wisely said ...

-- 
underground experts united
https://dataswamp.org/~incal

Re: filemananger for emacs with meta information about a file without opening it

[Jean Louis]

* tomas@tuxteam.de <tomas@tuxteam.de> [2022-11-03 10:58]:
> On Thu, Nov 03, 2022 at 09:49:17AM +0300, Jean Louis wrote:
> > * Uwe Brauer <oub@mat.ucm.es> [2022-10-31 23:50]:
> > > I am looking for a kind of «filemanager» for emacs, that allows me to
> > > obtain some meta information (about the content of the file) without
> > > opening it. 
> > 
> > In Dired, one uses `y' to get basic information about the file without
> > opening it. Often I use it for pictures to find out the resolution.
> 
> How do you find out a picture's resolution without opening the file?

Dired does it with library dired-aux.el, sorry, it is loaded on my
side automatically.

IMG_20100103_093721.jpg: JPEG image data, Exif standard: [\012- TIFF image data, little-endian, direntries=17, description=, manufacturer=meanIT, model=meanIT Q1 plus, orientation=upper-left, xresolution=314, yresolution=322, resolutionunit=2, software=MediaTek Camera Application, datetime=2010:01:03 09:37:22], baseline, precision 8, 2880x1728, components 3


-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

In support of Richard M. Stallman
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Re: filemananger for emacs with meta information about a file without opening it

[Jean Louis]

* Yuri Khan <yuri.v.khan@gmail.com> [2022-11-03 11:19]:
> On Thu, 3 Nov 2022 at 14:58, <tomas@tuxteam.de> wrote:
> 
> > > In Dired, one uses `y' to get basic information about the file without
> > > opening it. Often I use it for pictures to find out the resolution.
> >
> > How do you find out a picture's resolution without opening the file?
> 
> Nohow. The opening is just not perceived by the user. The pedantic
> description would probably be “without visiting in a buffer and
> without starting an associated interactive application”.

Of course something must read information in the file.

Other way to go is indexing pictures once and later searching within
the index.

-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

In support of Richard M. Stallman
https://stallmansupport.org/

RE: [External] : Re: filemananger for emacs with meta information about a file without opening it

[Drew Adams]

> I am looking for a kind of «filemanager» for emacs, that allows me to
> obtain some meta information (about the content of the file) without
> opening it.

Jean Louis mentioned Dired command `dired-show-file-type'
(which just runs GNU/Linux/shell command `file').

If you use Dired+ then that's bound by default to `_',
not `y' (`y' is `diredp-relsymlink-this-file').

If you use Dired+ and `help-fns+.el', then `C-h RET' is
`diredp-describe-file', which describes the file/dir of
the current line.  (Also `diredp-mouse-describe-file'.)

If the file/dir is a symlink then, with a non-negative
prefix arg, `C-h RET' describes the symlink target instead.

If you also use Bookmark+, and if the file has an
autofile bookmark, then `C-h RET' with a non-positive
prefix arg describes the bookmark too.

So a zero prefix arg describes symlink and bookmark.

(An autofile bookmark is automatically named with the
nondir part of the bookmarked file name.  It acts like
a file, but with additional, user-defined properties.)

E.g., if file `aaa.el' is on the current line, and it
has an autofile bookmark, then `C-h RET' shows something
like this:
_____________________________________________________

Bookmark `aaa.el'
-----------------

File:			aaa.el
Directory:		z:/foo/bar/toto/
Position:	          1
Visits:			5
Last visit:		7/30/2017 6:00:12 PM
Tags:
 "magenta"
 "orange"
 "blue"


z:/foo/bar/toto/aaa.el
----------------------

File type:                  Normal file
Content type:               Lisp/Scheme program, UTF-8 Unicode text
Permissions:                -rw-rw-rw-
Size in bytes:              96476
Time of last access:        Thu Nov  3 21:51:07 2022 (Pacific Daylight Time)
Time of last modification:  Thu Feb 27 09:04:48 2014 (Pacific Standard Time)
Time of last status change: Wed Jul 25 07:58:32 2018 (Pacific Daylight Time)
Number of links:            1
User ID (UID):              37786
Group ID (GID):             513
Inode:                      281474976868278
Device number:              315267003
_____________________________________________________

The "Content type" is whatever description the command
`dired-show-file-type' provides.
___

As for providing your own metadata for a file, which
some raised as a possibility, you can use a bookmark
annotation for that.  Any metadata you want.  It can
even refer to another file with more metadata, for
info you don't want to store as part of the bookmark.

Re: [External] : Re: filemananger for emacs with meta information about a file without opening it

[Uwe Brauer]

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>>> "DA" == Drew Adams <drew.adams@oracle.com> writes:


> If you also use Bookmark+, and if the file has an
> autofile bookmark, then `C-h RET' with a non-positive
> prefix arg describes the bookmark too.

> So a zero prefix arg describes symlink and bookmark.

> (An autofile bookmark is automatically named with the
> nondir part of the bookmarked file name.  It acts like
> a file, but with additional, user-defined properties.)

Thanks, I have used bookmark (without+) for ages and configured it for my workflow (using outline-minor-mode in a specific way).


Indeed I came across bookmark+ and dired+
When I started bookmark+ it looked (shockingly) different 🙃

I did not know about the keybinding you  described in dired mode which would be indeed helpful, thanks.

However I have also configured vanilla dired for my purposes, so I have to see whether that all would work under dired+.

The most important question is. Is there anyway to indicate in dired+ that a given file has a bookmark annotate entry?


It seems that I got finally https://github.com/gunther-bachmann/emacs-dired-annotator

To work, which takes a different route.

Thanks and regards

Uwe Brauer 

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Re: filemananger for emacs with meta information about a file without opening it

[Uwe Brauer]

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> Uwe Brauer wrote:

> Indeed, do it enough and often enough it doesn't have to
> be good.

> Quantity has its own quality, as Comrade Stalin wisely said ...

Yes, indeed he did say that, and that is why Russia lost roughly 5 times
as many soldiers and tanks as Germany (but won the war), well getting
off topic soon.........



-- 
Warning: Content may be disturbing to some audiences
I strongly condemn Putin's war of aggression against the Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the ban of Russia from SWIFT.
I support the EU membership of the Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/

[-- Attachment #2: smime.p7s --]
[-- Type: application/pkcs7-signature, Size: 5673 bytes --]

Re: filemananger for emacs with meta information about a file without opening it

[Eli Zaretskii]

> From: Uwe Brauer <oub@mat.ucm.es>
> Date: Fri, 04 Nov 2022 14:05:48 +0100
> 
> > Quantity has its own quality, as Comrade Stalin wisely said ...
> 
> Yes, indeed he did say that, and that is why Russia lost roughly 5 times
> as many soldiers and tanks as Germany (but won the war), well getting
> off topic soon.........

Would you please stop bringing up this stuff on this list?  Just your
signature is enough of irrelevant noise here; I wish you'd stopped
posting that mantra.  Its place is elsewhere, where these issues are
discussed and your opinions could actually change something.

RE: [External] : Re: filemananger for emacs with meta information about a file without opening it

[Drew Adams]

> Indeed I came across bookmark+ and dired+
> When I started bookmark+ it looked (shockingly) different 🙃

What shocks you?

The bookmark-list display looks a bit different
from vanilla bookmark.el.  Behavior of Bookmark+
is a superset of vanilla (additional features).
Vanilla bookmarks work with Bookmark+.

> The most important question is. Is there anyway to indicate
> in dired+ that a given file has a bookmark annotate entry?

Neither Bookmark+ nor Dired+ changes your file
names, and you needn't use any particular file
naming convention.

Autofiles can be highlighted specially in Dired,
and the highlighting indicates whether the file
is tagged.  Screenshot:

https://www.emacswiki.org/emacs/DrewsEmacsDiredAutofiles

Bookmarks need not have annotations.  Bookmark+
enhancements to annotations are described here:

https://www.emacswiki.org/emacs/BookmarkPlus#BookmarkAnnotations
 
___

Other URLs about this stuff:

https://www.emacswiki.org/emacs/BookmarkPlus#AutofileBookmarks

https://www.emacswiki.org/emacs/BookmarkPlus#TaggingFiles

https://www.emacswiki.org/emacs/BookmarkPlus#BookmarkTags

https://www.emacswiki.org/emacs/BookmarkPlus#HighlightingBookmarkLocations

https://www.emacswiki.org/emacs/DiredPlus

Re: filemananger for emacs with meta information about a file without opening it

[Marcin Borkowski]

On 2022-11-04, at 14:43, Eli Zaretskii <eliz@gnu.org> wrote:

>> From: Uwe Brauer <oub@mat.ucm.es>
>> Date: Fri, 04 Nov 2022 14:05:48 +0100
>>
>> > Quantity has its own quality, as Comrade Stalin wisely said ...
>>
>> Yes, indeed he did say that, and that is why Russia lost roughly 5 times
>> as many soldiers and tanks as Germany (but won the war), well getting
>> off topic soon.........
>
> Would you please stop bringing up this stuff on this list?  Just your
> signature is enough of irrelevant noise here; I wish you'd stopped
> posting that mantra.  Its place is elsewhere, where these issues are
> discussed and your opinions could actually change something.

Well, to be fair, he didn't start that this time.  Frankly, as someone
who lived in Poland (which was effectively under Stalin's rule for
significant amount of time, though luckily (for me) I wasn't born then
yet), seeing the words "Comrade Stalin" (with capital "C" even!) and
"wisely said" in direct vicinity made me almost physically cringe.  And
I'm actually pretty immune to things like this.

While I often appreciate Emanuel's quips, this one was bordering on
offensive...

Just my 2 cents,

-- 
Marcin Borkowski
http://mbork.pl

Re: [External] : Re: filemananger for emacs with meta information about a file without opening it

[Jean Louis]

* Drew Adams <drew.adams@oracle.com> [2022-11-04 08:15]:
> > I am looking for a kind of «filemanager» for emacs, that allows me to
> > obtain some meta information (about the content of the file) without
> > opening it.
> 
> Jean Louis mentioned Dired command `dired-show-file-type'
> (which just runs GNU/Linux/shell command `file').
> 
> If you use Dired+ then that's bound by default to `_',
> not `y' (`y' is `diredp-relsymlink-this-file').

For me, I am sorry now to forget your libraries. There are many of
them here, but dired+ was not loaded.

> Bookmark `aaa.el'
> -----------------
> 
> File:			aaa.el
> Directory:		z:/foo/bar/toto/
> Position:	          1
> Visits:			5
> Last visit:		7/30/2017 6:00:12 PM
> Tags:
>  "magenta"
>  "orange"
>  "blue"

There it is, full tagging system without renaming files. But where are
tags stored?

-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

In support of Richard M. Stallman
https://stallmansupport.org/

RE: [External] : Re: filemananger for emacs with meta information about a file without opening it

[Drew Adams]

> > Bookmark `aaa.el'
> > -----------------
> >
> > File:			aaa.el
> > Directory:		z:/foo/bar/toto/
> > Position:	          1
> > Visits:			5
> > Last visit:		7/30/2017 6:00:12 PM
> > Tags:
> >  "magenta"
> >  "orange"
> >  "blue"
>
>
> There it is, full tagging system without renaming files.
> But where are tags stored?

The tags for a bookmark are stored in the bookmark itself
(the bookmark record), under property `tags'.  See:

https://www.emacswiki.org/emacs/BookmarkPlus#BookmarkRecords

See here, for more description of tags, what their values
can be, and how you can use them:

https://www.emacswiki.org/emacs/BookmarkPlus#BookmarkTags

___

BTW, you say "full tagging system" - and you're right.
But I didn't say anything about that.  This tells you
about it:

https://www.emacswiki.org/emacs/BookmarkPlus#TagsAsAttributes

A tag is a string with any text - any length, any chars.
Beyond that, it can instead be a key-value pair: a cons
whose car is the tag name and whose cdr is an associated
value.  Here's a `tags' property from a bookmark record:

 (tags "bmkp-jump" ("bookmark-jump" lambda nil (message "Hello!"))
       "tata tuto titi"
       ("titi" . 42)
       ("foobar" foo bar)
       "beta"
       ("alpha"))

There are six tags there. Their names are "bmkp-jump",
"tata tuto titi", "titi", "foobar", "beta", and "alpha".

The value of "titi" is 42; the value of "foobar" is
`(foo bar)', the value of "alpha" is nil, and the value
of "bmkp-jump" is `("bookmark-jump" lambda nil (message
"Hello!"))'.  The tags named "tata tuto titi" and "beta"
have no associated value.  ("bmkp-jump" is a predefined
tag name - it's explained at the above link.)

___

BTW - Wrt the example you quoted above, I misspoke.
Instead of saying that a non-positive prefix arg means
include the autofile (bookmark) description, I should
have said this (from the `diredp-describe-file' doc):

  If the file has an autofile bookmark and you use
  library `Bookmark+', then show also the bookmark
  information (tags etc.).  In this case, a
  non-positive prefix arg shows the internal form
  of the bookmark.

So what that example shows is what you get with just
`C-h RET': if the file is an autofile then its description
includes the bookmark description.  With a non-positive
prefix arg you see the internal (i.e., Lisp) form of the
bookmark record:

_________________________________________

Bookmark `aaa.el'
-----------------

("aaa.el"
 (end-position . 1)
 (time 22910 33052 672000)
 (visits . 5)
 (tags "magenta" "orange" "blue")
 (filename . "z:/foo/bar/toto/aaa.el")
 (position . 1))


z:/foo/bar/toto/aaa.el
----------------------

File type:                  Normal file
Content type:               Lisp/Scheme program, UTF-8 Unicode text
Permissions:                -rw-rw-rw-
Size in bytes:              96476
Time of last access:        Sat Nov  5 13:17:36 2022 (Pacific Daylight Time)
Time of last modification:  Thu Feb 27 09:04:48 2014 (Pacific Standard Time)
Time of last status change: Wed Jul 25 07:58:32 2018 (Pacific Daylight Time)
Number of links:            1
User ID (UID):              37786
Group ID (GID):             513
Inode:                      281474976868278
Device number:              315267003
_________________________________________

Actually, by default the string that names the bookmark,
"aaa.el" in this example, is propertized, like this:

  #("aaa.el" 0 6 (bmkp-full-record #0))

That is, the bookmark name, which is the car of the
bookmark record, is a string with a property whose
value is the entire record (the cons whose car is that
string!).  This means the string itself is all that
any code needs, to get the full bookmark record.

(This is a kind of circular/self-referential object:
a list whose car is a string that contains that same
list as one of its text properties.  Another case of
Lisp chasing its tail.)

If the name is propertized then you can effectively
have more than one bookmark with the same name.

This is important, for example, for autofiles, whose
names are the nondir part of the file name.  You can
have the same autofile name for files with the same
name in different dirs.

Whether the name is thus propertized is controlled
by option `bmkp-propertize-bookmark-names-flag'.