bug#11881: 23.3; m-! pwd shows true path but dired buffer shows symbol linked path

[Aeron Wang]

This bug report will be sent to the Free Software Foundation,
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Please write in English if possible, because the Emacs maintainers
usually do not have translators to read other languages for them.

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and the gnu.emacs.bug news group, and at http://debbugs.gnu.org.

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug.  If you can, give
a recipe starting from `emacs -Q':


This is quite strange! and happened only occationally! I send this bug
report from the buffer happenly has the problem.

This is my journal of play with this problem... although nothing can
stop this problem, and I also not sure what caused it... but must be
Emacs, not shell.

> === notes begin ===

* TODO 20120708/7 in dired buf, do m-! pwd, or bash -c pwd, got absolute path, 
not the linked one.

when click S tabbar link to open Esession file:
edebug on file-truename:
  access-file("/tse_home/awang/myapp/GTAGS" "Reading directory")
  insert-directory("/tse_home/awang/myapp/GTAGS" "--dired -alh" t nil)
  dired-insert-directory("/tse_home/awang/myapp/GTAGS" "-alh" nil t t)
  dired-readin-insert()
  dired-readin()

(dired "~/myapp/GTAGS") --> some times it fails --> true.. actually no such dir 
at all!
(dired "/tse_home/awang/myapp/") --> this works
(dired "/tse_home/awang/myapp/emacs.data/GTAGS") --> this ok
(dired "~/myapp/emacs.data/GTAGS")

checked:
set -o --> no pysical set
shopt --> nothing special
find-file-visit-truename --> nil
find-file-existing-other-name --> nil

looks like the real dir is absolute, since: m-! pwd -L also shows absolute one. 
echo $PWD also absolute one. but default-directory and dired-directory is 
relatiev one.
- also, c-cs *shell* is also shows at absolute path! in *shell*, cd to linked 
path, do c-xc-f to show dired buf, it's still m-! pwd showing absolute!
  and:
  ELISP> (file-truename "~/mycvs/delme") --> ie file-truename already gone.
  "~/mycvs/delme"

did:
(defun file-truename (f) (message "true called on '%s'" f) f)
the same behavior even it's called.

even this the same behavior:
ELISP> (unload-feature 'dired t)
nil
ELISP> (unload-feature 'dired-aux t)
nil
ELISP> (unload-feature 'dired-x t)
nil
then -->
ELISP> (require 'dired)
dired
ELISP> (require 'dired-x)
dired-x
ELISP> (require 'dired-aux)
dired-aux
ELISP> (require 'files)
files
ELISP> (dired "~/myapp/")
#<buffer /tse_home/awang/myapp> --> still m-! pwd, giving absolute path!
did 'shell and 'comint; the same.

strange! strange!

no idea!!!

chk src on absolute:
directory-files
directory-files-and-attributes
ELISP> (expand-file-name "~/mycvs/delme")
"/tse_home/awang/mycvs/delme"
ELISP> (file-name-absolute-p "~/mycvs/delme")
t
ok.. looks absolute is not that... search file_truename:
buffer-file-truename is nil


even did this, the same:
ELISP> (defadvice file-truename (around  any-my-name-advice (f) activate 
compile)
(let ()
        (message "true called on '%s'" f)
        f
))
file-truename

even in IELM buf, c-cd to it frm delme3 dired, do m-! pwd, still got: 
/mnt/wk1/mycvs/delme3

vc-follow-symlinks nil --> even set to 'ask, the same.
vc-hooks.el: (vc-follow-link)

you do not need to debug bash or pwd, since the dir is really at 
/mnt/wk1/mycvs/delme3.
the issue is: why dired get there???

when *msg* current, m-! cd ~/mycvs;pwd ==> /tse_home/awang/mycvs
so looks it's an emacs issue.
when *dired* current, do above got true path.
ie looks dired goes to true path but it still shows symlink path.

del all bufs and do:
(dired "~/mycvs"), and m-! pwd, still got /mnt/wk1/..

frm that buf, did
report-emacs-bug and looks email sent out
> === end notes ===


If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/common/dev/awang/myapp/emacs233a/share/emacs/23.3/etc/DEBUG.


In GNU Emacs 23.3.1 (x86_64-unknown-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2011-11-18 on lnx
Windowing system distributor `The X.Org Foundation', version 11.0.60802000
configured using `configure  'CFLAGS= -g3 -O0' 
'--prefix=/common/dev/awang/myapp/emacs233a''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: en_US.utf-8
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.utf-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Dired by name

Minor modes in effect:
  shell-dirtrack-mode: t
  orgstruct-mode: t
  text-scale-mode: t

Recent input:
<down-mouse-1> <mouse-1> M-: ( C-y SPC - 1 ) <return> 
<help-echo> <help-echo> <down-mouse-5> <mouse-5> <down-mouse-5> 
<mouse-5> <down-mouse-1> <mouse-movement> <mouse-movement> 
<drag-mouse-1> M-: ( C-y SPC - 1 ) <return> <down-mouse-1> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<help-echo> <mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <help-echo> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <drag-mouse-1> C-c 
N C-y <help-echo> <down-mouse-4> <mouse-4> <down-mouse-4> 
<mouse-4> <down-mouse-4> <mouse-4> <down-mouse-1> <mouse-movement> 
<mouse-movement> <mouse-movement> <drag-mouse-1> M-% 
: SPC t <return> <return> ! M-< ( p <backspace> <backspace> 
C-M-% ^ <return> ( <return> ! \ <backspace> <backspace> 
<down-mouse-1> <mouse-movement> <mouse-movement> <drag-mouse-1> 
C-x r k <down-mouse-1> <mouse-movement> <mouse-movement> 
<drag-mouse-1> C-M-% $ <return> SPC - 1 ) <return> 
! <return> ) M-< <return> C-p ( p r o g n <down-mouse-1> 
<mouse-1> <down-mouse-1> <mouse-1> C-x C-e <help-echo> 
<help-echo> <help-echo> <down-mouse-5> <mouse-5> <down-mouse-5> 
<mouse-5> <down-mouse-5> <mouse-5> <double-down-mouse-5> 
<double-mouse-5> <down-mouse-1> <mouse-1> <down-mouse-5> 
<mouse-5> <double-down-mouse-5> <double-mouse-5> <down-mouse-5> 
<mouse-5> <down-mouse-5> <mouse-5> <down-mouse-1> <mouse-1> 
<down-mouse-1> <mouse-movement> <mouse-movement> <drag-mouse-1> 
<down-mouse-1> <mouse-movement> <drag-mouse-1> <down-mouse-5> 
<mouse-5> <down-mouse-5> <mouse-5> <down-mouse-1> <mouse-1> 
<down> <down> <down> <down> <down> <down> <help-echo> 
<down-mouse-2> <mouse-2> <down-mouse-4> <mouse-4> <down-mouse-4> 
<mouse-4> <down-mouse-1> <mouse-1> M-< M-< M-< C-n 
C-p C-n <down-mouse-1> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <mouse-movement> 
<mouse-movement> <mouse-movement> <drag-mouse-1> C-M-% 
. * C-b C-b <return> ( i n g <backspace> <backspace> 
g n o r e - e r r o r s SPC \ & ) <return> y ! <down-mouse-4> 
<mouse-4> <down-mouse-4> <mouse-4> <down-mouse-4> <mouse-4> 
<down-mouse-4> <mouse-4> <double-down-mouse-4> <double-mouse-4> 
<triple-down-mouse-4> <triple-mouse-4> <down-mouse-1> 
<mouse-1> M-< M-< M-< <down-mouse-1> <mouse-1> C-x 
C-e <down-mouse-1> <mouse-1> <double-down-mouse-1> 
<double-mouse-1> <help-echo> <down-mouse-1> <mouse-1> 
M-: M-p M-p M-p M-r d i r e d <return> ( C-e M-b C-b 
C-k SPC " ~ / m y c v s " ) <return> M-: M-! p w d 
<return> <help-echo> <help-echo> <help-echo> <down-mouse-2> 
<mouse-2> <down-mouse-1> <mouse-1> M-x M-p <return
>

Recent messages:
force to be writable
Replaced 19 occurrences
Replaced 20 occurrences
true called on 
'/tse_home/awang/myapp/emacs.data/GTAGS/emacs.el/emacs/lisp/rect.elc'
Replaced 19 occurrences
Entering debugger...
Replaced 19 occurrences
nil
#<buffer mycvs>
/mnt/wk1/mycvs

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