[NTLUG:Discuss] Symbolic link strangeness

[Kenneth Loafman]

P.S. - You'll find this happening in mounted filesystems as well.

There used to be a 'which' that told you if the command was a builtin,
but I think it was on the KSH or CSH shells.

example:
$ which pwd
'pwd' builtin
/bin/pwd

IIRC, you could prefix pwd with '%' or maybe '-' to force it to use the
native command.  It's been a long time, so I'm a bit rusty.

...Ken

Wayne Walker wrote:
> I left out.  This is discussed in "man bash".  But one must know that
> it's using bash instead of pwd.  I can't remember how to see if a
> command being used is a builtin or not.  "which" will NOT tell you :(
> 
> On Sun, Jun 11, 2006 at 08:16:18AM -0500, Wayne Walker wrote:
>> Leroy,
>>
>> you are using the pwd built into your shell, probably bash.  By default
>> it tells you "where you asked to go" not "where you are".
>>
>> To see where you really are, use /bin/pwd or pwd -P.
>>
>> The first uses the system program which won't lie to you.  The second
>> uses the bash builtin pwd and tells it to not lie to you.
>>
>> The third thing you can do is, at the command line, or better, in your
>> .bashrc file, "set -o physical" tells the bash builtin to not lie to
>> you.
>>
>> Wayne
>>
>> On Sat, Jun 10, 2006 at 11:30:33PM -0500, Leroy Tennison wrote:
>>> Trying to figure out kdm on CentOS 4.3.  Found:
>>>
>>> cd /usr/share/config/kdm
>>> [leroy at linux-b kdm]$ pwd
>>> /usr/share/config/kdm
>>> [leroy at linux-b kdm]$ ll Xsession
>>> lrwxrwxrwx  1 root root 22 May  7 05:08 Xsession -> ../../X11/xdm/Xsession
>>> [leroy at linux-b kdm]$ cd ../../X11/xdm
>>> [leroy at linux-b xdm]$ pwd
>>> /etc/X11/xdm                                    Hmmm, why am I not in 
>>> /usr/share/X11/xdm?
>>>
>>> After a little puzzlement and research
>>>
>>> [leroy at linux-b xdm]$ cd /usr/share/config
>>> [leroy at linux-b config]$ ll kdm
>>> lrwxrwxrwx  1 root root 20 May  7 05:08 kdm -> ../../../etc/kde/kdm
>>>
>>> OK, now the puzzlement above makes sense, so I decide to do
>>>
>>> [leroy at linux-b config]$ cd kdm
>>> [leroy at linux-b kdm]$ pwd
>>> /usr/share/config/kdm
>>>
>>> Why is pwd showing me /usr/share/config/kdm when I'm really in /etc/kde/kdm?
>>>
>>> I know that's where I am because (I had to su because the directory was 
>>> Read Only to all but root)
>>>
>>> [leroy at linux-b kdm]$ su
>>> Password:
>>> [root at linux-b kdm]# cat > LeRoY
>>> Where am I really?                                                   
>>> Ctrl-D on an empty line put me back at the prompt.
>>> [root at linux-b kdm]# ll L*
>>> -rw-r--r--  1 root root 19 Jun 10 23:19 LeRoY
>>> [root at linux-b kdm]# exit
>>> exit
>>> [leroy at linux-b kdm]$ cd /etc/kde/kdm
>>> [leroy at linux-b kdm]$ ll L*
>>> -rw-r--r--  1 root root 19 Jun 10 23:19 LeRoY
>>> [leroy at linux-b kdm]$ cat LeRoY
>>> Where am I really?
>>> [leroy at linux-b kdm]$ pwd
>>> /etc/kde/kdm
>>>
>>> What disturbs me about this is I can't trust the reply of pwd when a 
>>> symbolic link is a part of a path.  Is there another command I can use 
>>> to tell where I REALLY am instead of where I appear to be?  
>>> /usr/share/config/kdm doesn't really exist as a unique directory.
>>>
>>> _______________________________________________
>>> http://ntlug.pmichaud.com/mailman/listinfo/discuss
>> -- 
>>
>> Wayne Walker
>>
>> www.unwiredbuyer.com - when you just can't be by the computer
>>
>> wwalker at bybent.com                    Do you use Linux?!
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>