Re: BUG: /bin/pwd -P doesn't expand all symlinks

[Andrey Repin <anrdaemon@yandex.ru>]

Greetings, Mark O'Keefe!

> While using /bin/pwd -P to expand directories to get the absolute,
> non-symlinked version of the directory I discovered that this doesn't work
> on Cygwin as I believe it is meant to work.


> $ cd /tmp
> $ /bin/pwd -P
> /tmp
> $ ln -s /home .
> $ cd home
> $ /bin/pwd -P
> /home
> $ pwd
> /tmp/home
> $ mkdir dummy
> $ cd dummy
> $ pwd
> /tmp/home/dummy
> $ /bin/pwd -P
> /tmp/home/dummy

> NOTE:  That last command should have returned "/home/dummy".  It hasn't
> expanded the parent symbolic link as you would have expected it to do.

> For what I'm doing I need the physical path, not the symbolic path (which is what the -P is meant to provide).

> Please confirm if I'm correct in my understanding?  I've tested this on
> Ubuntu and it works as I'd expect it...

> Now having to create an alternative approach to get the correct answer
> while I wait for this to be fixed (assuming it is a bug as I believe it is).

> Thanks in advance for any help in resolving this.

There's some juju with native symlink expansion going on. I vaguely recall
that it was done for speed. But the results really seems non-expected.

C:\arc is a symlink to the \\daemon1\arc shared directory.

$ cd /c/arc/
anrdaemon@daemon2:/c/arc
$ /bin/pwd.exe -P
//DAEMON1/arc
anrdaemon@daemon2:/c/arc
$ /bin/readlink.exe -fe .
//DAEMON1/arc

All is well.

anrdaemon@daemon2:/c/arc
$ cd images/
anrdaemon@daemon2:/c/arc/images
$ /bin/pwd.exe -P
/c/arc/images
anrdaemon@daemon2:/c/arc/images
$ readlink -fe .
/c/arc/images

Not expected. But here we are going to real surprise:

anrdaemon@daemon2:/c/arc/images
$ readlink -fe $(pwd)
//DAEMON1/arc/images


-- 
With best regards,
Andrey Repin
Friday, October 23, 2015 17:46:32

Sorry for my terrible english...


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