patch for Dired second header line info

patch for Dired second header line info

[Drew Adams]

[-- Attachment #1: Type: text/plain, Size: 1739 bytes --]

The second header line in a Dired buffer currently looks like this:

 total used in directory 49439 available 56233408

Attached is a patch (for `files.el' and `ls-lisp.el') that changes that text
to this:

 files 691 space used 49439 available 56233408

IOW, it adds the number of files and directories (`files'), and it shortens
`total used in directory' to `space used'. That also makes it clearer what
"total used" means (total what?). We might want to change `space used' to
`Kbytes used' or whatever, to be even clearer.

Entries `.' and `..' are not counted, but other directories are, along with
non-directory files. The patch works for `-lR' listings also, updating the
subdir totals.

Room for improvement: 

1. Like the current code, this code replaces the initial text `total' that
is written to the buffer. Perhaps we could just write the correct text to
begin with, instead of doing a text substitution for the placeholder
`total'?

2. The proposed code does this:
(add-hook 'dired-after-readin-hook
          'update-dired-files-count)

Perhaps we could do the `update-dired-files-count' directly in the code that
runs the hook, instead?

As it stands now, the file count and the space counts are updated only
during directory read-in - e.g. when you hit `g' (nothing new in that, BTW).
I could not find a hook for when a file or dir is added/deleted (or
hidden/shown), etc. Wouldn't it be useful to have a hook for whenever the
Dired display changes? 


Here's a change-log entry:

2008-02-29 Drew Adams  <drew.adams@oracle.com>
	* files.el:
	(insert-directory): Print number of files.
	(count-dired-files): New function.
	(update-dired-files-count): New function.
	* ls-lisp.el (insert-directory): Print number of files.


[-- Attachment #2: ls-lisp-2008-02-29.patch --]
[-- Type: application/octet-stream, Size: 1434 bytes --]

diff -c -w "ls-lisp-CVS-2008-02-29.el" "ls-lisp-patched-2008-02-29.el"
*** ls-lisp-CVS-2008-02-29.el	Fri Feb 29 14:58:50 2008
--- ls-lisp-patched-2008-02-29.el	Fri Feb 29 15:01:32 2008
***************
*** 263,274 ****
  	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  ;; First find the line to put it on.
! 	  (when (re-search-forward "^total" nil t)
! 	    (let ((available (get-free-disk-space ".")))
  	      (when available
- 		;; Replace "total" with "total used", to avoid confusion.
- 		(replace-match "total used in directory")
  		(end-of-line)
  		(insert " available " available)))))))))
  
--- 263,279 ----
  	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  (while (re-search-forward "^total" nil t)
!             (beginning-of-line)
!             (insert "files "
!                     (number-to-string (save-match-data (count-dired-files)))
!                     " ")
!             (goto-char (point-min))
!             (re-search-forward "^files [0-9]+ \\(total\\)" nil t)
!             (replace-match "space used" nil nil nil 1)
! 	    (let ((available (and (fboundp 'get-free-disk-space)
!                                   (get-free-disk-space "."))))
  	      (when available
  		(end-of-line)
  		(insert " available " available)))))))))
  

Diff finished at Fri Feb 29 15:19:17

[-- Attachment #3: files-2008-02-29.patch --]
[-- Type: application/octet-stream, Size: 3667 bytes --]

diff -c -w files-CVS-2008-02-29.el" "files-patched-2008-02-29.el"
*** files-CVS-2008-02-29.el	Fri Feb 29 14:59:08 2008
--- files-patched-2008-02-29.el	Fri Feb 29 15:17:20 2008
***************
*** 5284,5303 ****
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 
! 	  (if full-directory-p
! 	      ;; Try to insert the amount of free space.
  	      (save-excursion
  		(goto-char beg)
! 		;; First find the line to put it on.
! 		(when (re-search-forward "^ *\\(total\\)" nil t)
! 		  (let ((available (get-free-disk-space ".")))
  		    (when available
- 		      ;; Replace "total" with "used", to avoid confusion.
- 		      (replace-match "total used in directory" nil nil nil 1)
  		      (end-of-line)
  		      (insert " available " available)))))))))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
  File name position values returned in ls --dired output
--- 5284,5336 ----
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 	  (when full-directory-p
              (save-excursion
                (goto-char beg)
!               (while (re-search-forward "^ *\\(total\\)" nil t)
!                 (beginning-of-line)
!                 (insert "files " (number-to-string (save-match-data
!                                                      (count-dired-files)))
!                         " ")
!                 (goto-char beg)
!                 (re-search-forward "^files [0-9]+ \\(total\\)" nil t)
!                 (replace-match "space used" nil nil nil 1)
!                 (let ((available (and (fboundp 'get-free-disk-space)
!                                       (get-free-disk-space "."))))
                    (when available
                      (end-of-line)
                      (insert " available " available)))))))))))
  
+ (defun count-dired-files ()
+   "Returns the number of files in the current Dired directory listing.
+ This includes directory entries, as well as files, but it excludes `.'
+ and `..'."
+   ;; Should we skip `#' files also, as in `dired-trivial-filenames'? Dunno.
+   (save-excursion
+     (re-search-backward "^$" nil 'to-bob)
+     (re-search-forward dired-move-to-filename-regexp nil t)
+     (let* ((beg (line-beginning-position))
+            (end (save-excursion (re-search-forward "^$" nil t)))
+            (dots-p (save-excursion      ; Is `..' present?
+                      (goto-char beg)
+                      (re-search-forward
+                       (concat directory-listing-before-filename-regexp
+                               "\\.\\./?$")
+                       end t))))
+       (if dots-p (- (count-lines beg end) 2) (count-lines beg end)))))
+ 
+ (add-hook 'dired-after-readin-hook 'update-dired-files-count)
+ (defun update-dired-files-count ()
+   "Update file count in Dired header for each directory listed."
+   (let ((num-files (number-to-string (count-dired-files))))
+     (save-excursion
+       (goto-char (point-min))
+       (while (re-search-forward "^  files \\([0-9]+\\)" nil t)
+         (let ((buffer-read-only nil))
+           (replace-match (number-to-string (save-match-data (count-dired-files)))
+                          nil nil nil 1))
+         (set-buffer-modified-p nil)))))
+ 
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
  File name position values returned in ls --dired output

Diff finished at Fri Feb 29 15:17:44

Re: patch for Dired second header line info

[Richard Stallman]

The "files 691" may be misleading if it means the number
of files listed in this dired buffer, rather than the number
in the directory.

RE: patch for Dired second header line info

[Drew Adams]

> The "files 691" may be misleading if it means the number
> of files listed in this dired buffer, rather than the number
> in the directory.

True, just as it might be misleading because it says "files" instead of
"files and directories". And it doesn't say "in this directory" instead of
"in this directory and below". And the space indication doesn't say "in this
directory" for the used space and "on the whole disk" for available space.

That's why we have doc. We can change the label if you like. But if this
wasn't a problem before, for "total used" (total what? what units? in what
scope?) and "available (ditto, and the scope here is presumably the disk,
not the dir), then I don't think it will be much of a problem now.

I think it's good to keep the labels short, but you can change it to, say,
"files listed" or "files shown". You might also want to use a colon after
each label, some commas, and perhaps title case. This is clearer, perhaps -
shorten as desired:

 Files & dirs shown: 691, Kbytes used in dir: 49439, Kbytes available on
disk: 56233408

Personally, I think it's clear enough as is, but it should be mentioned in
the doc somewhere - I don't think it is mentioned at all now. Also, someone
using wildcards or hiding lines will discover soon enough that the "files"
figure changes.

Re: patch for Dired second header line info

[Richard Stallman]

    > The "files 691" may be misleading if it means the number
    > of files listed in this dired buffer, rather than the number
    > in the directory.

    True, just as it might be misleading because it says "files" instead of
    "files and directories". And it doesn't say "in this directory" instead of
    "in this directory and below". And the space indication doesn't say "in this
    directory" for the used space and "on the whole disk" for available space.

Each of these is a different issue.  Each one of these might or might
not be confusing.  The answer to one question is not the answer to
all.

    I think it's good to keep the labels short, but you can change it to, say,
    "files listed"

That sounds like a big improvement.

Re: patch for Dired second header line info

[Juri Linkov]

> The second header line in a Dired buffer currently looks like this:
>
>  total used in directory 49439 available 56233408
>
> Attached is a patch (for `files.el' and `ls-lisp.el') that changes that text
> to this:
>
>  files 691 space used 49439 available 56233408

Are you sure this change will not break other packages that rely on the
first word `total' at the beginning of a dired buffer?  It seems it would
be safer to leave it as is, and add new information to the end of this line
like:

total used in directory 49439 available 56233408 files 691

Also I think instead of displaying the number of files listed in the
current dired buffer, more useful would be to display the total number of
files in the current directory.  There are features that hide files in the
dired buffer (e.g. dired-omit-mode), so displaying the total number of
files will be helpful for users to see that there are more hidden files.
This also will simplify the implementation of the feature you propose,
so instead of a new function `count-dired-files' you can just use
(length (directory-files dir nil t))

-- 
Juri Linkov
http://www.jurta.org/emacs/

RE: patch for Dired second header line info

[Drew Adams]

> > The second header line in a Dired buffer currently looks like this:
> >
> >  total used in directory 49439 available 56233408
> >
> > Attached is a patch (for `files.el' and `ls-lisp.el') that 
> > changes that text to this:
> >
> >  files 691 space used 49439 available 56233408
> 
> Are you sure this change will not break other packages that 
> rely on the first word `total' at the beginning of a dired
> buffer?

How could I (or anyone) be sure of that? Who knows what some package might
rely on?

> It seems it would be safer to leave it as is, and
> add new information to the end of this line like:
> 
> total used in directory 49439 available 56233408 files 691

Go for it, if you think that's right.

I think that the text I used is clearer - see my comments about "total" and
"used"/"available". And if some package were to break because of my proposed
change, then we would fix the code as needed. 

If things are so fragile that we don't dare change text such as this, then
the design is wrong. In fact, the right way to do this kind of thing is to
use a function or variable instead of hard-coded text. But a change to do
that might also break some package somewhere. (if omelette (break eggs))

But do as you like.

> Also I think instead of displaying the number of files listed
> in the current dired buffer, more useful would be to display
> the total number of files in the current directory. There are
> features that hide files in the dired buffer (e.g.
> dired-omit-mode), so displaying the total number of
> files will be helpful for users to see that there are more 
> hidden files.

I disagree - it's a feature, not a bug, to see how many files are currently
visible.

For example, if I use Dired with wildcards, I want to see how many matching
files there are. If I hide the files with extension `elc', I want to see how
many files are left. And so on. The figure should reflect the current
display state.

BTW, I did not check until now, but that is also apparently the approach
Windows Explorer uses (FWIW). If you hide system files, for instance, the
file count excludes them.

> This also will simplify the implementation of the feature you propose,
> so instead of a new function `count-dired-files' you can just use
> (length (directory-files dir nil t))

I purposefully avoided that approach, preferring to have it tell you how
many files were currently visible.

But do whatever you like with it. Whatever semantics you choose, the doc
needs to make clear what the meaning is. Likewise for the other fields.

Actually, instead of changing the patch, please ignore it and leave the code
as it is. At least that way my extension will continue to work for me. ;-)

Re: patch for Dired second header line info

[Juri Linkov]

>> Are you sure this change will not break other packages that
>> rely on the first word `total' at the beginning of a dired
>> buffer?
>
> How could I (or anyone) be sure of that? Who knows what some package might
> rely on?

Using one of several code search engines, for instance,
http://www.krugle.org/kse/files?query=%22total+used%22&lang=elisp
you can find a few packages that rely on the format of this string,
including your ls-lisp+.el http://www.emacswiki.org/cgi-bin/wiki/ls-lisp%2B.el.

>> Also I think instead of displaying the number of files listed
>> in the current dired buffer, more useful would be to display
>> the total number of files in the current directory. There are
>> features that hide files in the dired buffer (e.g.
>> dired-omit-mode), so displaying the total number of
>> files will be helpful for users to see that there are more
>> hidden files.
>
> I disagree - it's a feature, not a bug, to see how many files are currently
> visible.
>
> For example, if I use Dired with wildcards, I want to see how many matching
> files there are. If I hide the files with extension `elc', I want to see how
> many files are left. And so on. The figure should reflect the current
> display state.

Sorry, it didn't appear to me that the number of listed files would be
useful too.  But we can display both numbers on the same line using the
traditional notation "listed/total", e.g.

total used in directory 49439 available 56233408 files 691/1000

> BTW, I did not check until now, but that is also apparently the approach
> Windows Explorer uses (FWIW). If you hide system files, for instance, the
> file count excludes them.

BTW, such file managers also display the number and total size of selected
files.  I have a function `dired-count-marked-files' that does the same
and displays this information in the echo area after marking a file.

Maybe instead of the echo area and instead of the header line beginning
with `total' we could display this information in the mode line?

There is a special mode-line symbol %i and %I (`size-indication-mode')
that is not very useful in dired mode.  We could use it (or create a new
%-construct) to display the total number of selected/all files and their
sizes in the mode line in more concise format.

-- 
Juri Linkov
http://www.jurta.org/emacs/

RE: patch for Dired second header line info

[Drew Adams]

> >> Are you sure this change will not break other packages that
> >> rely on the first word `total' at the beginning of a dired
> >> buffer?
> >
> > How could I (or anyone) be sure of that? Who knows what 
> > some package might rely on?
> 
> Using one of several code search engines, for instance,
> http://www.krugle.org/kse/files?query=%22total+used%22&lang=elisp
> you can find a few packages that rely on the format of this string,
> including your ls-lisp+.el 
> http://www.emacswiki.org/cgi-bin/wiki/ls-lisp%2B.el.

1. It was a rhetorical question. 

The right way is to use a function or variable, and external packages can
then adapt. Avoiding hard-coding would also facilitate translation and other
transformations. If there are libraries today that depend on "total" at the
beginning of the line, it is because they have no choice.

2. My package ls-lisp+.el is 1/2 of the patch I sent. The other half is in
files+.el. 

IOW, ls-lisp+.el is not an example of an existing package that will be
broken by my patch - it _is_ my patch. (These libraries let users of older
Emacs users also have the new feature.)

> >> Also I think instead of displaying the number of files listed
> >> in the current dired buffer, more useful would be to display
> >> the total number of files in the current directory. There are
> >> features that hide files in the dired buffer (e.g.
> >> dired-omit-mode), so displaying the total number of
> >> files will be helpful for users to see that there are more
> >> hidden files.
> >
> > I disagree - it's a feature, not a bug, to see how many 
> > files are currently visible.
> >
> > For example, if I use Dired with wildcards, I want to see 
> > how many matching files there are. If I hide the files with
> > extension `elc', I want to see how many files are left.
> > And so on. The figure should reflect the current
> > display state.
> 
> Sorry, it didn't appear to me that the number of listed files would be
> useful too.  But we can display both numbers on the same line 
> using the traditional notation "listed/total", e.g.
> 
> total used in directory 49439 available 56233408 files 691/1000

Good idea. Go for it. And perhaps that will obviate the need for `files
listed' instead of `files'.

I still prefer the order I suggested, and shortening and clarifying `total
used in directory' to `space used' or `kbytes used'.

> > BTW, I did not check until now, but that is also apparently 
> > the approach Windows Explorer uses (FWIW). If you hide system
> > files, for instance, the file count excludes them.
> 
> BTW, such file managers also display the number and total 
> size of selected files.

Yes. I agree that `files 691/1000' is preferable.

BTW, if the meanings of `space used' and `available' were comparable, we
could do the same thing there. But one is presumably the space used in the
directory, and the other is presumably the space available on the disk, so
two labels are needed in that case.

> I have a function `dired-count-marked-files' that 
> does the same and displays this information in the echo area
> after marking a file.
> 
> Maybe instead of the echo area and instead of the header line 
> beginning with `total' we could display this information in the
> mode line?

That was in fact the starting point for my patch: a help-gnu-emacs question
was answered by a post from Kevin Rodgers that used the mode line that way.

I specifically want to avoid putting such stuff in the mode line -
especially in the minor-mode lighter list. The lighter list has a specific
meaning that should not be muddied, and the list is already busy enough. I
typically have 3 or 4 minor modes active at the same time. 

It's true that we already do that kind of thing in some modes (e.g. `grep'),
but I think it's bad practice in general and should not be expanded. And
this file/space info is not as important as the info we put in the `grep'
lighter. A temporary indication of something can sometimes be appropriate in
a lighter area, but we shouldn't turn lighters into essays or status lines.

Would you also add the space used/available to the Dired lighter? And would
you list the used/available figures for every inserted subdir in the mode
line? This is a bad idea, IMO.

So no, I disagree that the mode line is a good place to put this info.

> There is a special mode-line symbol %i and %I (`size-indication-mode')
> that is not very useful in dired mode.  We could use it (or 
> create a new %-construct) to display the total number of selected/all 
> files and their sizes in the mode line in more concise format.

I vote against it. Just one vote.

RE: patch for Dired second header line info

[Drew Adams]

[-- Attachment #1: Type: text/plain, Size: 500 bytes --]

> > Sorry, it didn't appear to me that the number of listed 
> > files would be useful too.  But we can display both numbers on
> > the same line using the traditional notation "listed/total"...
> 
> Good idea. Go for it. And perhaps that will obviate the need 
> for `files listed' instead of `files'.

Attached: patch for this. The text is now:

  files 420/694 space used 19646 available 56456000

Meaning: 420 files shown now, out of 694 total in the directory. Subdirs are
treated the same way.

[-- Attachment #2: files-2008-03-02.patch --]
[-- Type: application/octet-stream, Size: 3805 bytes --]

diff -c -w "files-CVS-2008-02-29.el" "files-patched-2008-03-02.el"
*** files-CVS-2008-02-29.el	Fri Feb 29 14:59:08 2008
--- files-patched-2008-03-02.el	Sun Mar  2 09:39:54 2008
***************
*** 5284,5303 ****
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 
! 	  (if full-directory-p
! 	      ;; Try to insert the amount of free space.
  	      (save-excursion
  		(goto-char beg)
! 		;; First find the line to put it on.
! 		(when (re-search-forward "^ *\\(total\\)" nil t)
! 		  (let ((available (get-free-disk-space ".")))
  		    (when available
- 		      ;; Replace "total" with "used", to avoid confusion.
- 		      (replace-match "total used in directory" nil nil nil 1)
  		      (end-of-line)
  		      (insert " available " available)))))))))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
  File name position values returned in ls --dired output
--- 5284,5338 ----
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 	  (when full-directory-p
              (save-excursion
                (goto-char beg)
!               (while (re-search-forward "^ *\\(total\\)" nil t)
!                 (beginning-of-line)
!                 (insert "files " (number-to-string (save-match-data
!                                                      (count-dired-files)))
!                         "/" (number-to-string
!                              (- (length (directory-files file nil nil t)) 2))
!                         " ")
!                 (goto-char beg)
!                 (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!                 (replace-match "space used" nil nil nil 1)
!                 (let ((available (and (fboundp 'get-free-disk-space)
!                                       (get-free-disk-space "."))))
                    (when available
                      (end-of-line)
                      (insert " available " available)))))))))))
  
+ (defun count-dired-files ()
+   "Returns the number of files in the current Dired directory listing.
+ This includes directory entries, as well as files, but it excludes `.'
+ and `..'."
+   ;; Should we skip `#' files also, as in `dired-trivial-filenames'? Dunno.
+   (save-excursion
+     (re-search-backward "^$" nil 'to-bob)
+     (re-search-forward dired-move-to-filename-regexp nil t)
+     (let* ((beg (line-beginning-position))
+            (end (save-excursion (re-search-forward "^$" nil t)))
+            (dots-p (save-excursion      ; Is `..' present?
+                      (goto-char beg)
+                      (re-search-forward
+                       (concat directory-listing-before-filename-regexp
+                               "\\.\\./?$")
+                       end t))))
+       (if dots-p (- (count-lines beg end) 2) (count-lines beg end)))))
+ 
+ (add-hook 'dired-after-readin-hook 'update-dired-files-count)
+ (defun update-dired-files-count ()
+   "Update file count in Dired header for each directory listed."
+   (let ((num-files (number-to-string (count-dired-files))))
+     (save-excursion
+       (goto-char (point-min))
+       (while (re-search-forward "^  files \\([0-9]+\\)" nil t)
+         (let ((buffer-read-only nil))
+           (replace-match (number-to-string (save-match-data (count-dired-files)))
+                          nil nil nil 1))
+         (set-buffer-modified-p nil)))))
+ 
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
  File name position values returned in ls --dired output

Diff finished at Sun Mar 02 09:41:59

[-- Attachment #3: ls-lisp-2008-03-02.patch --]
[-- Type: application/octet-stream, Size: 1592 bytes --]

diff -c -w "ls-lisp-CVS-2008-02-29.el" "ls-lisp-patched-2008-03-02.el"
*** ls-lisp-CVS-2008-02-29.el	Fri Feb 29 14:58:50 2008
--- ls-lisp-patched-2008-03-02.el	Sun Mar  2 09:41:04 2008
***************
*** 263,274 ****
  	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  ;; First find the line to put it on.
! 	  (when (re-search-forward "^total" nil t)
! 	    (let ((available (get-free-disk-space ".")))
  	      (when available
- 		;; Replace "total" with "total used", to avoid confusion.
- 		(replace-match "total used in directory")
  		(end-of-line)
  		(insert " available " available)))))))))
  
--- 263,281 ----
  	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  (while (re-search-forward "^total" nil t)
!             (beginning-of-line)
!             (insert "files " (number-to-string (save-match-data
!                                                  (count-dired-files)))
!                     "/" (number-to-string
!                          (- (length (directory-files file nil nil t)) 2))
!                     " ")
!             (goto-char (point-min))
!             (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!             (replace-match "space used" nil nil nil 1)
! 	    (let ((available (and (fboundp 'get-free-disk-space)
!                                   (get-free-disk-space "."))))
  	      (when available
  		(end-of-line)
  		(insert " available " available)))))))))
  

Diff finished at Sun Mar 02 09:43:22

Re: patch for Dired second header line info

[Juri Linkov]

>> > Sorry, it didn't appear to me that the number of listed
>> > files would be useful too.  But we can display both numbers on
>> > the same line using the traditional notation "listed/total"...
>>
>> Good idea. Go for it. And perhaps that will obviate the need
>> for `files listed' instead of `files'.
>
> Attached: patch for this. The text is now:
>
>   files 420/694 space used 19646 available 56456000

The string `total' is the standard string printed by `ls' so maybe we
should keep it.  Also what do you think about further compacting
this line as:

total files 420/694 space 19646/56456000

or using the same function in `size-indication-mode' that displays the
size in the mode line in human-readable format:

total files 420/694 space 19KB/56MB

Also we could add a tooltip explaining what these numbers mean if they
are not obvious.

> Meaning: 420 files shown now, out of 694 total in the directory. Subdirs are
> treated the same way.

In your patch maybe better to move dired functionality to dired.el or
dired-aux.el and rename `count-dired-files' to `dired-count-files'.

-- 
Juri Linkov
http://www.jurta.org/emacs/

RE: patch for Dired second header line info

[Drew Adams]

[-- Attachment #1: Type: text/plain, Size: 1322 bytes --]

> > Attached: patch for this. The text is now:
> >
> >   files 420/694 space used 19646 available 56456000
> 
> The string `total' is the standard string printed by `ls' so maybe we
> should keep it.  Also what do you think about further compacting
> this line as:
> 
> total files 420/694 space 19646/56456000

I already said that I find "total" unclear and I prefer the form I proposed.

> or using the same function in `size-indication-mode' that displays the
> size in the mode line in human-readable format:
> 
> total files 420/694 space 19KB/56MB

That might be OK, but what's wrong with giving a more precise number? That's
typically what is given for this kind of thing.

> Also we could add a tooltip explaining what these numbers mean if they
> are not obvious.
> 
> > Meaning: 420 files shown now, out of 694 total in the 
> directory. Subdirs are
> > treated the same way.

Great minds think alike. I was already doing that - new patch attached.
(Also fixed a bug introduced in last patch.)

(The text should say nothing about subdirs, BTW - each subdir has its own
tooltip.)

> In your patch maybe better to move dired functionality to dired.el or
> dired-aux.el and rename `count-dired-files' to `dired-count-files'.

I'll leave that to others to decide. My proposal just leaves things where
they are now.


[-- Attachment #2: files-2008-03-02b.patch --]
[-- Type: application/octet-stream, Size: 4039 bytes --]

diff -c -w files-CVS-2008-02-29.el files-patched-2008-03-02b.el
*** files-CVS-2008-02-29.el	Fri Feb 29 14:59:08 2008
--- files-patched-2008-03-02b.el	Sun Mar  2 10:49:54 2008
***************
*** 5284,5302 ****
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 
! 	  (if full-directory-p
! 	      ;; Try to insert the amount of free space.
  	      (save-excursion
  		(goto-char beg)
! 		;; First find the line to put it on.
! 		(when (re-search-forward "^ *\\(total\\)" nil t)
! 		  (let ((available (get-free-disk-space ".")))
  		    (when available
- 		      ;; Replace "total" with "used", to avoid confusion.
- 		      (replace-match "total used in directory" nil nil nil 1)
  		      (end-of-line)
! 		      (insert " available " available)))))))))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
--- 5284,5342 ----
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 	  (when full-directory-p
              (save-excursion
                (goto-char beg)
!               (while (re-search-forward "^ *\\(total\\)" nil t)
!                 (beginning-of-line)
!                 (insert "files " (number-to-string (save-match-data
!                                                      (count-dired-files)))
!                         "/" (number-to-string
!                              (- (length (directory-files default-directory
!                                                          nil nil t)) 2))
!                         " ")
!                 (goto-char beg)
!                 (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!                 (replace-match "space used" nil nil nil 1)
!                 (let ((available (and (fboundp 'get-free-disk-space)
!                                       (get-free-disk-space "."))))
                    (when available
                      (end-of-line)
!                     (insert " available " available)))
!                 (put-text-property (progn (beginning-of-line) (point))
!                                    (progn (end-of-line) (point))
!                                    'help-echo "Files shown, total files in \
! dir, Kbytes used in dir, Kbytes available on disk")))))))))
! 
! (defun count-dired-files ()
!   "Returns the number of files in the current Dired directory listing.
! This includes directory entries, as well as files, but it excludes `.'
! and `..'."
!   ;; Should we skip `#' files also, as in `dired-trivial-filenames'? Dunno.
!   (save-excursion
!     (re-search-backward "^$" nil 'to-bob)
!     (re-search-forward dired-move-to-filename-regexp nil t)
!     (let* ((beg (line-beginning-position))
!            (end (save-excursion (re-search-forward "^$" nil t)))
!            (dots-p (save-excursion      ; Is `..' present?
!                      (goto-char beg)
!                      (re-search-forward
!                       (concat directory-listing-before-filename-regexp
!                               "\\.\\./?$")
!                       end t))))
!       (if dots-p (- (count-lines beg end) 2) (count-lines beg end)))))
! 
! (add-hook 'dired-after-readin-hook 'update-dired-files-count)
! (defun update-dired-files-count ()
!   "Update file count in Dired header for each directory listed."
!   (let ((num-files (number-to-string (count-dired-files))))
!     (save-excursion
!       (goto-char (point-min))
!       (while (re-search-forward "^  files \\([0-9]+\\)" nil t)
!         (let ((buffer-read-only nil))
!           (replace-match (number-to-string (save-match-data (count-dired-files)))
!                          nil nil nil 1))
!         (set-buffer-modified-p nil)))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.

Diff finished.  Sun Mar 02 10:53:36 2008

[-- Attachment #3: ls-lisp-2008-03-02b.patch --]
[-- Type: application/octet-stream, Size: 2360 bytes --]

diff -c -w ls-lisp-CVS-2008-02-29.el ls-lisp-patched-2008-03-02b.el
*** ls-lisp-CVS-2008-02-29.el	Fri Feb 29 14:58:50 2008
--- ls-lisp-patched-2008-03-02b.el	Sun Mar  2 10:51:18 2008
***************
*** 260,276 ****
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
- 	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  ;; First find the line to put it on.
! 	  (when (re-search-forward "^total" nil t)
! 	    (let ((available (get-free-disk-space ".")))
  	      (when available
- 		;; Replace "total" with "total used", to avoid confusion.
- 		(replace-match "total used in directory")
  		(end-of-line)
! 		(insert " available " available)))))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)
--- 260,287 ----
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
  	(save-excursion
  	  (goto-char (point-min))
! 	  (while (re-search-forward "^total" nil t)
!             (beginning-of-line)
!             (insert "files " (number-to-string (save-match-data
!                                                  (count-dired-files)))
!                     "/" (number-to-string
!                          (- (length (directory-files default-directory
!                                                      nil nil t)) 2))
!                     " ")
!             (goto-char (point-min))
!             (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!             (replace-match "space used" nil nil nil 1)
! 	    (let ((available (and (fboundp 'get-free-disk-space)
!                                   (get-free-disk-space "."))))
                (when available
                  (end-of-line)
!                 (insert " available " available)))
!             (put-text-property (progn (beginning-of-line) (point))
!                                (progn (end-of-line) (point))
!                                'help-echo "Files shown, total files in \
! dir, Kbytes used in dir, Kbytes available on disk")))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)

Diff finished.  Sun Mar 02 10:51:42 2008

RE: patch for Dired second header line info

[Drew Adams]

[-- Attachment #1: Type: text/plain, Size: 196 bytes --]

> Great minds think alike. I was already doing that - new patch 
> attached. (Also fixed a bug introduced in last patch.)

Sorry, I forgot to include that bug fix in the files.el patch. Attached.

[-- Attachment #2: files-2008-03-02c.patch --]
[-- Type: application/octet-stream, Size: 4289 bytes --]

diff -c -w "files-CVS-2008-02-29.el" "files-patched-2008-03-02c.el"
*** files-CVS-2008-02-29.el	Fri Feb 29 14:59:08 2008
--- files-patched-2008-03-02c.el	Sun Mar  2 11:02:58 2008
***************
*** 5284,5302 ****
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 
! 	  (if full-directory-p
! 	      ;; Try to insert the amount of free space.
  	      (save-excursion
  		(goto-char beg)
! 		;; First find the line to put it on.
! 		(when (re-search-forward "^ *\\(total\\)" nil t)
! 		  (let ((available (get-free-disk-space ".")))
  		    (when available
- 		      ;; Replace "total" with "used", to avoid confusion.
- 		      (replace-match "total used in directory" nil nil nil 1)
  		      (end-of-line)
! 		      (insert " available " available)))))))))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
--- 5284,5346 ----
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 	  (when full-directory-p
              (save-excursion
                (goto-char beg)
!               (while (re-search-forward "^ *\\(total\\)" nil t)
!                 (beginning-of-line)
!                 (insert "files " (number-to-string (save-match-data
!                                                      (count-dired-files)))
!                         "/" (number-to-string
!                              (- (length (directory-files default-directory
!                                                          nil nil t)) 2))
!                         " ")
!                 (goto-char beg)
!                 (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!                 (replace-match "space used" nil nil nil 1)
!                 (let ((available (and (fboundp 'get-free-disk-space)
!                                       (get-free-disk-space "."))))
                    (when available
                      (end-of-line)
!                     (insert " available " available)))
!                 (put-text-property (progn (beginning-of-line) (point))
!                                    (progn (end-of-line) (point))
!                                    'help-echo "Files shown, total files in \
! dir, Kbytes used in dir, Kbytes available on disk")))))))))
! 
! (defun count-dired-files ()
!   "Returns the number of files in the current Dired directory listing.
! This includes directory entries, as well as files, but it excludes `.'
! and `..'."
!   ;; Should we skip `#' files also, as in `dired-trivial-filenames'? Dunno.
!   (save-excursion
!     (re-search-backward "^$" nil 'to-bob)
!     (re-search-forward dired-move-to-filename-regexp nil t)
!     (let* ((beg (line-beginning-position))
!            (end (save-excursion (re-search-forward "^$" nil t)))
!            (dots-p (save-excursion      ; Is `..' present?
!                      (goto-char beg)
!                      (re-search-forward
!                       (concat directory-listing-before-filename-regexp
!                               "\\.\\./?$")
!                       end t))))
!       (if dots-p (- (count-lines beg end) 2) (count-lines beg end)))))
! 
! (add-hook 'dired-after-readin-hook 'update-dired-files-count)
! (defun update-dired-files-count ()
!   "Update file count in Dired header for each directory listed."
!   (let ((num-files (number-to-string (count-dired-files))))
!     (save-excursion
!       (goto-char (point-min))
!       (while (re-search-forward "^  files \\([0-9]+\\)/\\([0-9]+\\)" nil t)
!         (let ((buffer-read-only nil))
!           (replace-match (number-to-string (save-match-data (count-dired-files)))
!                          nil nil nil 1)
!           (replace-match (number-to-string
!                           (- (length (directory-files default-directory
!                                                       nil nil t)) 2))
!                          nil nil nil 2))
!         (set-buffer-modified-p nil)))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.

Diff finished at Sun Mar 02 11:03:47

[-- Attachment #3: ls-lisp-2008-03-02b.patch --]
[-- Type: application/octet-stream, Size: 2360 bytes --]

diff -c -w ls-lisp-CVS-2008-02-29.el ls-lisp-patched-2008-03-02b.el
*** ls-lisp-CVS-2008-02-29.el	Fri Feb 29 14:58:50 2008
--- ls-lisp-patched-2008-03-02b.el	Sun Mar  2 10:51:18 2008
***************
*** 260,276 ****
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
- 	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  ;; First find the line to put it on.
! 	  (when (re-search-forward "^total" nil t)
! 	    (let ((available (get-free-disk-space ".")))
  	      (when available
- 		;; Replace "total" with "total used", to avoid confusion.
- 		(replace-match "total used in directory")
  		(end-of-line)
! 		(insert " available " available)))))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)
--- 260,287 ----
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
  	(save-excursion
  	  (goto-char (point-min))
! 	  (while (re-search-forward "^total" nil t)
!             (beginning-of-line)
!             (insert "files " (number-to-string (save-match-data
!                                                  (count-dired-files)))
!                     "/" (number-to-string
!                          (- (length (directory-files default-directory
!                                                      nil nil t)) 2))
!                     " ")
!             (goto-char (point-min))
!             (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!             (replace-match "space used" nil nil nil 1)
! 	    (let ((available (and (fboundp 'get-free-disk-space)
!                                   (get-free-disk-space "."))))
                (when available
                  (end-of-line)
!                 (insert " available " available)))
!             (put-text-property (progn (beginning-of-line) (point))
!                                (progn (end-of-line) (point))
!                                'help-echo "Files shown, total files in \
! dir, Kbytes used in dir, Kbytes available on disk")))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)

Diff finished.  Sun Mar 02 10:51:42 2008

RE: patch for Dired second header line info

[Drew Adams]

[-- Attachment #1: Type: text/plain, Size: 1542 bytes --]

New patch attached, for consideration as an alternative to the previous one.
They are the same except for the following new feature, which you might or
might not like:

The directory info line has mouse-face highlighting. Hitting RET or clicking
mouse-2 on it displays more info about the directory, in buffer *Help*.

This is what the *Help* display looks like:

 Properties of `c:/foobar':

 Type:                       Directory
 Permissions:                drwxrwxrwx
 Time of last access:        Sun Mar  2 00:00:00 2008 (Pacific Standard
Time)
 Time of last modification:  Tue Aug 21 19:21:00 2007 (Pacific Standard
Time)
 Time of last status change: Tue Aug 21 19:20:59 2007 (Pacific Standard
Time)
 Number of links:            1
 User ID (UID):              5
 Group ID (GID):             5
 Inode:                      26687
 Device number:              240391127

 [back]

Obviously, a different choice could be made for the time format. Just as
obviously, some of this info is already displayed in the Dired buffer,
unless you use `dired-details-hide' (did that ever get added to Emacs?) to
hide the details.

The help commands involved are general. I added them to files.el, but you
might want to do one or more of the following:

1. Move `describe-file' to help-fns.el (and bind it to, say, `C-h M-f').
2. Move `dired(-mouse)-describe-file' to dired.el.
3. Move `dired(-mouse)-describe-listed-directory' to dired.el.

The commands in #3 are used only in `insert-directory', however, so you
might prefer to keep them in files.el.

[-- Attachment #2: ls-lisp-2008-03-02c.patch --]
[-- Type: application/octet-stream, Size: 2729 bytes --]

diff -c -w ls-lisp-CVS-2008-02-29.el ls-lisp-patched-2008-03-02c.el
*** ls-lisp-CVS-2008-02-29.el	Fri Feb 29 14:58:50 2008
--- ls-lisp-patched-2008-03-02c.el	Sun Mar  2 15:53:20 2008
***************
*** 260,276 ****
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
- 	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  ;; First find the line to put it on.
! 	  (when (re-search-forward "^total" nil t)
! 	    (let ((available (get-free-disk-space ".")))
  	      (when available
- 		;; Replace "total" with "total used", to avoid confusion.
- 		(replace-match "total used in directory")
  		(end-of-line)
! 		(insert " available " available)))))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)
--- 260,295 ----
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
  	(save-excursion
  	  (goto-char (point-min))
! 	  (while (re-search-forward "^total" nil t)
!             (beginning-of-line)
!             (insert "files " (number-to-string (save-match-data
!                                                  (count-dired-files)))
!                     "/" (number-to-string
!                          (- (length (directory-files default-directory
!                                                      nil nil t)) 2))
!                     " ")
!             (goto-char (point-min))
!             (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!             (replace-match "space used" nil nil nil 1)
! 	    (let ((available (and (fboundp 'get-free-disk-space)
!                                   (get-free-disk-space "."))))
                (when available
                  (end-of-line)
!                 (insert " available " available)))
!             (add-text-properties
!              (save-excursion (beginning-of-line) (point))
!              (save-excursion (end-of-line) (point))
!              `(mouse-face highlight
!                keymap
!                ,(let ((map (make-sparse-keymap)))
!                      (define-key map [mouse-2]
!                        'dired-mouse-describe-listed-directory)
!                      (define-key map "\r" 'dired-describe-listed-directory)
!                      map)
!                help-echo "Files shown, total files in dir, Kbytes \
! used in dir, Kbytes available on disk [RET, mouse-2: more info]"))))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)

Diff finished.  Sun Mar 02 15:53:46 2008

[-- Attachment #3: files-2008-03-02d.patch --]
[-- Type: application/octet-stream, Size: 9008 bytes --]

diff -c -w "files-CVS-2008-02-29.el" "files-patched-2008-03-02e.el"
*** files-CVS-2008-02-29.el	Fri Feb 29 14:59:08 2008
--- files-patched-2008-03-02e.el	Sun Mar  2 16:31:56 2008
***************
*** 5284,5302 ****
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 
! 	  (if full-directory-p
! 	      ;; Try to insert the amount of free space.
  	      (save-excursion
  		(goto-char beg)
! 		;; First find the line to put it on.
! 		(when (re-search-forward "^ *\\(total\\)" nil t)
! 		  (let ((available (get-free-disk-space ".")))
  		    (when available
- 		      ;; Replace "total" with "used", to avoid confusion.
- 		      (replace-match "total used in directory" nil nil nil 1)
  		      (end-of-line)
! 		      (insert " available " available)))))))))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
--- 5284,5446 ----
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 	  (when full-directory-p
              (save-excursion
                (goto-char beg)
!               (while (re-search-forward "^ *\\(total\\)" nil t)
!                 (beginning-of-line)
!                 (insert "files " (number-to-string (save-match-data
!                                                      (count-dired-files)))
!                         "/" (number-to-string
!                              (- (length (directory-files default-directory
!                                                          nil nil t)) 2))
!                         " ")
!                 (goto-char beg)
!                 (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!                 (replace-match "space used" nil nil nil 1)
!                 (let ((available (and (fboundp 'get-free-disk-space)
!                                       (get-free-disk-space "."))))
                    (when available
                      (end-of-line)
!                     (insert " available " available)))
!                 (add-text-properties
!                  (save-excursion (beginning-of-line) (point))
!                  (save-excursion (end-of-line) (point))
!                  `(mouse-face highlight
!                    keymap
!                    ,(let ((map (make-sparse-keymap)))
!                          (define-key map [mouse-2]
!                            'dired-mouse-describe-listed-directory)
!                          (define-key map "\r" 'dired-describe-listed-directory)
!                          map)
!                    help-echo "Files shown, total files in dir, Kbytes \
! used in dir, Kbytes available on disk [RET, mouse-2: more info]"))))))))))
! 
! (defun count-dired-files ()
!   "Returns the number of files in the current Dired directory listing.
! This includes directory entries, as well as files, but it excludes `.'
! and `..'."
!   ;; Should we skip `#' files also, as in `dired-trivial-filenames'? Dunno.
!   (save-excursion
!     (re-search-backward "^$" nil 'to-bob)
!     (re-search-forward dired-move-to-filename-regexp nil t)
!     (let* ((beg (line-beginning-position))
!            (end (save-excursion (re-search-forward "^$" nil t)))
!            (dots-p (save-excursion      ; Is `..' present?
!                      (goto-char beg)
!                      (re-search-forward
!                       (concat directory-listing-before-filename-regexp
!                               "\\.\\./?$")
!                       end t))))
!       (if dots-p (- (count-lines beg end) 2) (count-lines beg end)))))
! 
! (add-hook 'dired-after-readin-hook 'update-dired-files-count)
! (defun update-dired-files-count ()
!   "Update file count in Dired header for each directory listed."
!   (let ((num-files (number-to-string (count-dired-files))))
!     (save-excursion
!       (goto-char (point-min))
!       (while (re-search-forward "^  files \\([0-9]+\\)/\\([0-9]+\\)" nil t)
!         (let ((buffer-read-only nil))
!           (replace-match (number-to-string (save-match-data (count-dired-files)))
!                          nil nil nil 1)
!           (replace-match (number-to-string
!                           (- (length (directory-files default-directory
!                                                       nil nil t)) 2))
!                          nil nil nil 2)
!           (add-text-properties
!            (save-excursion (beginning-of-line) (point))
!            (save-excursion (end-of-line) (point))
!            `(mouse-face highlight
!              keymap
!              ,(let ((map (make-sparse-keymap)))
!                    (define-key map [mouse-2]
!                      'dired-mouse-describe-listed-directory)
!                    (define-key map "\r" 'dired-describe-listed-directory)
!                    map)
!              help-echo "Files shown, total files in dir, Kbytes \
! used in dir, Kbytes available on disk [RET, mouse-2: more info]")))
!         (set-buffer-modified-p nil)))))
! 
! (defun dired-describe-listed-directory ()
!   "In Dired, describe the current listed directory."
!   (interactive)
!   (let ((dirname (save-excursion
!                    (forward-line -1)
!                    (skip-syntax-forward " ")
!                    (buffer-substring
!                     (point)
!                     (save-excursion (end-of-line) (1- (point))))))) ; Up to colon.
!     
!     (describe-file dirname)))
! 
! (defun dired-mouse-describe-listed-directory (event)
!   "Describe the current listed directory."
!   (interactive "e")
!   (save-excursion
!     (set-buffer (window-buffer (posn-window (event-end event))))
!     (goto-char (posn-point (event-end event)))
!     (dired-describe-listed-directory)))
! 
! (defun dired-describe-file ()
!   "In Dired, describe this file or directory."
!   (interactive)
!   (describe-file (dired-get-filename nil t)))
! 
! (defun dired-mouse-describe-file (event)
!   "Describe the clicked file."
!   (interactive "e")
!   (let (file)
!     (save-excursion
!       (set-buffer (window-buffer (posn-window (event-end event))))
!       (goto-char (posn-point (event-end event)))
!       (setq file (dired-get-filename nil t)))
!     (describe-file file)))
! 
! ;; This is the same definition as in `help-fns+.el' and `help+20.el'.
! (defun describe-file (filename)
!   "Describe the file named FILENAME.
! If FILENAME is nil, describe the current directory."
!   (interactive "FDescribe file: ")
!   (unless filename (setq filename default-directory))
!   (help-setup-xref (list #'describe-file filename) (interactive-p))
!   (let ((attrs (file-attributes filename)))
!     (unless attrs (error(format "Cannot open file `%s'" filename)))
!     (let* ((type            (nth 0 attrs))
!            (numlinks        (nth 1 attrs))
!            (uid             (nth 2 attrs))
!            (gid             (nth 3 attrs))
!            (last-access     (nth 4 attrs))
!            (last-mod        (nth 5 attrs))
!            (last-status-chg (nth 6 attrs))
!            (size            (nth 7 attrs))
!            (permissions     (nth 8 attrs))
!            ;; Skip 9: t iff file's gid would change if file were deleted
!            ;; and recreated.
!            (inode           (nth 10 attrs))
!            (device          (nth 11 attrs))
!            (help-text
!             (concat
!              (format "Properties of `%s':\n\n" filename)
!              (format "Type:                       %s\n"
!                      (cond ((eq t type) "Directory")
!                            ((stringp type) (format "Symbolic link to `%s'" type))
!                            (t "Normal file")))
!              (format "Permissions:                %s\n" permissions)
!              (and (not (eq t type)) (format "Size in bytes:              %g\n" size))
!              (format-time-string
!               "Time of last access:        %a %b %e %T %Y (%Z)\n" last-access)
!              (format-time-string
!               "Time of last modification:  %a %b %e %T %Y (%Z)\n" last-mod)
!              (format-time-string
!               "Time of last status change: %a %b %e %T %Y (%Z)\n" last-status-chg)
!              (format "Number of links:            %d\n" numlinks)
!              (format "User ID (UID):              %s\n" uid)
!              (format "Group ID (GID):             %s\n" gid)
!              (format "Inode:                      %S\n" inode)
!              (format "Device number:              %s\n" device))))
!       (with-output-to-temp-buffer "*Help*" (princ help-text))
!       help-text)))                      ; Return displayed text.
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.

Diff finished at Sun Mar 02 16:32:32

Re: patch for Dired second header line info

[Richard Stallman]

    The string `total' is the standard string printed by `ls' so maybe we
    should keep it.  Also what do you think about further compacting
    this line as:

    total files 420/694 space 19646/56456000

That is extremely misleading, since the first is
VISIBLE/IN-DIR and the second is IN-DIR/TOTAL.
In other words, the 694 is analogous to the 19646,
but 694 comes second in a pair, while 19646 comes first in a pair.

    Also we could add a tooltip explaining what these numbers mean if they
    are not obvious.

Using a tooltip to explain could be a good idea, but we
should still try to make it clearer in the text.
There is no shortage of space in that line.

Re: patch for Dired second header line info

[Stefan Monnier]

>     total files 420/694 space 19646/56456000

> That is extremely misleading, since the first is
> VISIBLE/IN-DIR and the second is IN-DIR/TOTAL.
> In other words, the 694 is analogous to the 19646,
> but 694 comes second in a pair, while 19646 comes first in a pair.

I believe it's worse than that:  it's not IN-DIR/TOTAL but
BYES-USED-IN-DIR/BYTES-LEFT-ON-DISK, i.e. the second number may be
smaller than the first.


        Stefan

RE: patch for Dired second header line info

[Drew Adams]

> >     total files 420/694 space 19646/56456000
> 
> > That is extremely misleading, since the first is
> > VISIBLE/IN-DIR and the second is IN-DIR/TOTAL.
> > In other words, the 694 is analogous to the 19646,
> > but 694 comes second in a pair, while 19646 comes first in a pair.
> 
> I believe it's worse than that:  it's not IN-DIR/TOTAL but
> BYES-USED-IN-DIR/BYTES-LEFT-ON-DISK, i.e. the second number may be
> smaller than the first.

That was my guess also. Which is why, although I used "files 420/694", I
used "space used 19646 available 56456000".

The tooltip also helps:

"Files shown, total files in dir, Kbytes used in dir, Kbytes available on
disk [RET, mouse-2: more info]"

IMO, it's not worth adding a lot of text for this to the buffer, but a
tooltip can help clarify things - for example, that "space used" refers to
the directory, but "available" refers to free disk space (independent of any
directory).

Re: patch for Dired second header line info

[Richard Stallman]

    The tooltip also helps:

    "Files shown, total files in dir, Kbytes used in dir, Kbytes available on
    disk [RET, mouse-2: more info]"

Each number should have its own tooltip which explains that number
and not the others.

RE: patch for Dired second header line info

[Drew Adams]

>     The tooltip also helps:
> 
>     "Files shown, total files in dir, Kbytes used in dir, 
>     Kbytes available on disk [RET, mouse-2: more info]"
> 
> Each number should have its own tooltip which explains that number
> and not the others.

Sorry; I don't agree. The meanings of the numbers are related (similar), at
least in pairs. Four separate tooltips would be more an annoyance than a
help, because the similarities and differences can't be grasped without a
silly back-and-forth:

420: Number of files and subdirectories currently shown in directory

694: Number of files and subdirectories in directory, including hidden ones

19646: Kbytes used in directory

56456000: Kbytes available (free) on disk

To understand 420 or 694, for instance, you would need to go back and forth
between their tooltips, trying to remember what the non-displayed tooltip
said while reading the displayed one, and comparing them mentally, in order
to grasp the difference.

Two tooltips, for the two pairs, might be reasonable, however.

In any case, change it however you like.

RE: patch for Dired second header line info

[Drew Adams]

[-- Attachment #1: Type: text/plain, Size: 1742 bytes --]

> >     The tooltip also helps:
> > 
> >     "Files shown, total files in dir, Kbytes used in dir, 
> >     Kbytes available on disk [RET, mouse-2: more info]"
> > 
> > Each number should have its own tooltip which explains that number
> > and not the others.
> 
> Sorry; I don't agree. The meanings of the numbers are related 
> (similar), at
> least in pairs. Four separate tooltips would be more an 
> annoyance than a
> help, because the similarities and differences can't be 
> grasped without a
> silly back-and-forth:
> 
> 420: Number of files and subdirectories currently shown in directory
> 
> 694: Number of files and subdirectories in directory, 
> including hidden ones
> 
> 19646: Kbytes used in directory
> 
> 56456000: Kbytes available (free) on disk
> 
> To understand 420 or 694, for instance, you would need to go 
> back and forth between their tooltips, trying to remember what the 
> non-displayed tooltip said while reading the displayed one, and
> comparing them mentally, in order to grasp the difference.
> 
> Two tooltips, for the two pairs, might be reasonable, however.
> 
> In any case, change it however you like.

1. OK, attached is a patch that does what I suggested (two tooltips, not 1
or 4).

2. The patch also fixes the problem of not updating when you perform update
operations, such as add a file or directory.

However, there remains a case where updating does not refresh the info line:
file deletion. For some reason, `dired-after-readin-hook' is not run when
you delete files.

Is that perhaps a dired bug, or is it by design?
`dired-internal-do-deletions' is called whether you flag a file and then use
`x' or you mark it and then use `D'. Should `dired-internal-do-deletions'
run the hook? 

HTH.

[-- Attachment #2: files-2008-03-04a.patch --]
[-- Type: application/octet-stream, Size: 9006 bytes --]

diff -c -w "files-CVS-2008-02-29.el" "files-patched-2008-03-04a.el"
*** files-CVS-2008-02-29.el	Fri Feb 29 14:59:08 2008
--- files-patched-2008-03-04a.el	Tue Mar  4 14:04:36 2008
***************
*** 5284,5302 ****
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 
! 	  (if full-directory-p
! 	      ;; Try to insert the amount of free space.
  	      (save-excursion
  		(goto-char beg)
! 		;; First find the line to put it on.
! 		(when (re-search-forward "^ *\\(total\\)" nil t)
! 		  (let ((available (get-free-disk-space ".")))
! 		    (when available
! 		      ;; Replace "total" with "used", to avoid confusion.
! 		      (replace-match "total used in directory" nil nil nil 1)
! 		      (end-of-line)
! 		      (insert " available " available)))))))))))
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.
--- 5284,5444 ----
  		      (if val
  			  (put-text-property pos (point)
  					     'dired-filename t)))))))
! 	  (when full-directory-p
!             (save-excursion
!               (goto-char beg)
!               (while (re-search-forward "^ *\\(total\\)" nil t)
!                 (beginning-of-line)
!                 (insert "files " (number-to-string (save-match-data
!                                                      (count-dired-files)))
!                         "/" (number-to-string
!                              (- (length (directory-files default-directory
!                                                          nil nil t)) 2))
!                         " ")
!                 (goto-char beg)
!                 (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!                 (replace-match "space used" nil nil nil 1)
!                 (let ((available (and (fboundp 'get-free-disk-space)
!                                       (get-free-disk-space ".")))
!                       (map (make-sparse-keymap)))
!                   (define-key map [mouse-2] 'dired-mouse-describe-listed-directory)
!                   (define-key map "\r" 'dired-describe-listed-directory)
!                   (when available (end-of-line) (insert " available " available))
!                   (add-text-properties
!                    (save-excursion (beginning-of-line) (+ 2 (point)))
!                    (1- (match-beginning 1))
!                    `(mouse-face highlight keymap ,map
!                      help-echo "Files shown / total files in directory \
! \[RET, mouse-2: more info]"))
!                   (add-text-properties
!                    (match-beginning 1) (save-excursion (end-of-line) (point))
!                    `(mouse-face highlight keymap ,map
!                      help-echo "Kbytes used in directory, Kbytes \
! available on disk [RET, mouse-2: more info]")))))))))))
! 
! (defun count-dired-files ()
!   "Returns the number of files in the current Dired directory listing.
! This includes directory entries, as well as files, but it excludes `.'
! and `..'."
!   ;; Should we skip `#' files also, as in `dired-trivial-filenames'? Dunno.
    (save-excursion
+     (re-search-backward "^$" nil 'to-bob)
+     (re-search-forward dired-move-to-filename-regexp nil t)
+     (let* ((beg (line-beginning-position))
+            (end (save-excursion (re-search-forward "^$" nil t)))
+            (dots-p (save-excursion      ; Is `..' present?
                       (goto-char beg)
!                      (re-search-forward
!                       (concat directory-listing-before-filename-regexp
!                               "\\.\\./?$")
!                       end t))))
!       (if dots-p (- (count-lines beg end) 2) (count-lines beg end)))))
! 
! (add-hook 'dired-after-readin-hook 'update-dired-files-count)
! (defun update-dired-files-count ()
!   "Update file count in Dired header for each directory listed."
!   (save-restriction
!     (widen)
!     (let ((num-files (number-to-string (count-dired-files))))
!       (save-excursion
!         (goto-char (point-min))
!         (while (re-search-forward "^  files \\([0-9]+\\)/\\([0-9]+\\)" nil t)
!           (let ((buffer-read-only nil)
!                 (map (make-sparse-keymap)))
!             (define-key map [mouse-2] 'dired-mouse-describe-listed-directory)
!             (define-key map "\r" 'dired-describe-listed-directory)
!             (replace-match (number-to-string (save-match-data (count-dired-files)))
!                            nil nil nil 1)
!             (replace-match (number-to-string
!                             (- (length (directory-files default-directory
!                                                         nil nil t)) 2))
!                            nil nil nil 2)
!             (add-text-properties
!              (save-excursion (beginning-of-line) (+ 2 (point))) (match-end 2)
!              `(mouse-face highlight keymap ,map
!                help-echo "Files shown / total files in directory \
! \[RET, mouse-2: more info]")))
!           (set-buffer-modified-p nil))))))
! 
! (defun dired-describe-listed-directory ()
!   "In Dired, describe the current listed directory."
!   (interactive)
!   (let ((dirname (save-excursion
!                    (forward-line -1)
!                    (skip-syntax-forward " ")
!                    (buffer-substring
!                     (point)
!                     (save-excursion (end-of-line) (1- (point))))))) ; Up to colon.
!     
!     (describe-file dirname)))
! 
! (defun dired-mouse-describe-listed-directory (event)
!   "Describe the current listed directory."
!   (interactive "e")
!   (save-excursion
!     (set-buffer (window-buffer (posn-window (event-end event))))
!     (goto-char (posn-point (event-end event)))
!     (dired-describe-listed-directory)))
! 
! (defun dired-describe-file ()
!   "In Dired, describe this file or directory."
!   (interactive)
!   (describe-file (dired-get-filename nil t)))
! 
! (defun dired-mouse-describe-file (event)
!   "Describe the clicked file."
!   (interactive "e")
!   (let (file)
!     (save-excursion
!       (set-buffer (window-buffer (posn-window (event-end event))))
!       (goto-char (posn-point (event-end event)))
!       (setq file (dired-get-filename nil t)))
!     (describe-file file)))
! 
! ;; This is the same definition as in `help-fns+.el' and `help+20.el'.
! (defun describe-file (filename)
!   "Describe the file named FILENAME.
! If FILENAME is nil, describe the current directory."
!   (interactive "FDescribe file: ")
!   (unless filename (setq filename default-directory))
!   (help-setup-xref (list #'describe-file filename) (interactive-p))
!   (let ((attrs (file-attributes filename)))
!     (unless attrs (error(format "Cannot open file `%s'" filename)))
!     (let* ((type            (nth 0 attrs))
!            (numlinks        (nth 1 attrs))
!            (uid             (nth 2 attrs))
!            (gid             (nth 3 attrs))
!            (last-access     (nth 4 attrs))
!            (last-mod        (nth 5 attrs))
!            (last-status-chg (nth 6 attrs))
!            (size            (nth 7 attrs))
!            (permissions     (nth 8 attrs))
!            ;; Skip 9: t iff file's gid would change if file were deleted
!            ;; and recreated.
!            (inode           (nth 10 attrs))
!            (device          (nth 11 attrs))
!            (help-text
!             (concat
!              (format "Properties of `%s':\n\n" filename)
!              (format "Type:                       %s\n"
!                      (cond ((eq t type) "Directory")
!                            ((stringp type) (format "Symbolic link to `%s'" type))
!                            (t "Normal file")))
!              (format "Permissions:                %s\n" permissions)
!              (and (not (eq t type)) (format "Size in bytes:              %g\n" size))
!              (format-time-string
!               "Time of last access:        %a %b %e %T %Y (%Z)\n" last-access)
!              (format-time-string
!               "Time of last modification:  %a %b %e %T %Y (%Z)\n" last-mod)
!              (format-time-string
!               "Time of last status change: %a %b %e %T %Y (%Z)\n" last-status-chg)
!              (format "Number of links:            %d\n" numlinks)
!              (format "User ID (UID):              %s\n" uid)
!              (format "Group ID (GID):             %s\n" gid)
!              (format "Inode:                      %S\n" inode)
!              (format "Device number:              %s\n" device))))
!       (with-output-to-temp-buffer "*Help*" (princ help-text))
!       help-text)))                      ; Return displayed text.
  
  (defun insert-directory-adj-pos (pos error-lines)
    "Convert `ls --dired' file name position value POS to a buffer position.

[-- Attachment #3: ls-lisp-2008-03-04a.patch --]
[-- Type: application/octet-stream, Size: 2911 bytes --]

diff -c -w "ls-lisp-CVS-2008-02-29.el" "ls-lisp-patched-2008-03-04a.el"
*** ls-lisp-CVS-2008-02-29.el	Fri Feb 29 14:58:50 2008
--- ls-lisp-patched-2008-03-04a.el	Tue Mar  4 14:03:20 2008
***************
*** 260,276 ****
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
- 	;; Try to insert the amount of free space.
  	(save-excursion
  	  (goto-char (point-min))
! 	  ;; First find the line to put it on.
! 	  (when (re-search-forward "^total" nil t)
! 	    (let ((available (get-free-disk-space ".")))
! 	      (when available
! 		;; Replace "total" with "total used", to avoid confusion.
! 		(replace-match "total used in directory")
! 		(end-of-line)
! 		(insert " available " available)))))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)
--- 260,298 ----
  		  file switches (ls-lisp-time-index switches)
  		  nil full-directory-p))
  	     (signal (car err) (cdr err)))))
  	(save-excursion
  	  (goto-char (point-min))
! 	  (while (re-search-forward "^total" nil t)
!             (beginning-of-line)
!             (insert "files " (number-to-string (save-match-data
!                                                  (count-dired-files)))
!                     "/" (number-to-string
!                          (- (length (directory-files default-directory
!                                                      nil nil t)) 2))
!                     " ")
!             (goto-char (point-min))
!             (re-search-forward "^files [0-9]+/[0-9]+ \\(total\\)" nil t)
!             (replace-match "space used" nil nil nil 1)
!             (let ((available (and (fboundp 'get-free-disk-space)
!                                   (get-free-disk-space ".")))
!                   (map (make-sparse-keymap)))
!               (define-key map [mouse-2]
!                 'dired-mouse-describe-listed-directory)
!               (define-key map "\r" 'dired-describe-listed-directory)
!               (when available (end-of-line) (insert " available "
!                                                     available))
!               (add-text-properties
!                (save-excursion (beginning-of-line) (+ 2 (point)))
!                (1- (match-beginning 1))
!                `(mouse-face highlight keymap ,map
!                  help-echo "Files shown / total files in directory \
! \[RET, mouse-2: more info]"))
!               (add-text-properties
!                (match-beginning 1)
!                (save-excursion (end-of-line) (point))
!                `(mouse-face highlight keymap ,map
!                  help-echo "Kbytes used in directory, Kbytes \
! available on disk [RET, mouse-2: more info]")))))))))
  
  (defun ls-lisp-insert-directory
    (file switches time-index wildcard-regexp full-directory-p)

Re: patch for Dired second header line info

[Richard Stallman]

    > Each number should have its own tooltip which explains that number
    > and not the others.

    Sorry; I don't agree. The meanings of the numbers are related (similar), at
    least in pairs. Four separate tooltips would be more an annoyance than a
    help, because the similarities and differences can't be grasped without a
    silly back-and-forth:

I am not convinced, but I won't argue about it.

Re: patch for Dired second header line info

[Richard Stallman]

      files 420/694 space used 19646 available 56456000

I think

      files shown 420 in dir 694 their size 19646 available 56456000

is cleaner, for the usual case where the buffer shows one
directory (or a subset of it).

Does the "files shown" get updated by all the Dired commands
that alter which files are shown?  If not, I think it is misleading.

RE: patch for Dired second header line info

[Drew Adams]

>       files 420/694 space used 19646 available 56456000
> I think
>       files shown 420 in dir 694 their size 19646 available 56456000
> 
> is cleaner, for the usual case where the buffer shows one
> directory (or a subset of it).

Feel free to adjust it as you like. 

BTW, what you propose works not only for the usual case, but also for any
included subdirs. Each subdir listing has its own such info line.

> Does the "files shown" get updated by all the Dired commands
> that alter which files are shown?  If not, I think it is misleading.

No, unfortunately. I use `dired-after-readin-hook' to trigger the update,
because I don't know of a better way. But that hook is sometimes run without
all the files being shown (for some reason).

For example, if you use `+' to create a directory, the hook is run with only
the new directory shown. However, in that case, the directory header is also
now showing, so it is at least not updated incorrectly to 1 - it remains
(incorrectly) what it was before the `+'.

Anyone know of a better hook to use for this or a better way to trigger the
update?

Wrt it being misleading: If no better implementation is found, to have it
update automatically in all cases (e.g. chmod, deletion, file copy,...),
then the doc should say that it is updated only when the directory is read
in. It should be enough to say that you can use `g' at any time to update
the files figures.

Re: patch for Dired second header line info

[Juri Linkov]

> It's true that we already do that kind of thing in some modes (e.g. `grep'),
> but I think it's bad practice in general and should not be expanded. And
> this file/space info is not as important as the info we put in the `grep'
> lighter. A temporary indication of something can sometimes be appropriate in
> a lighter area, but we shouldn't turn lighters into essays or status lines.
>
> Would you also add the space used/available to the Dired lighter? And would
> you list the used/available figures for every inserted subdir in the mode line?

No, I would only add the number/size of marked files as a temporary indication.

-- 
Juri Linkov
http://www.jurta.org/emacs/