Here's the case. I have a directory call :- %/home/myname/
I did a soft link in that directory:- %cd /home/myname/ %ln -s /home/others/ .
Now, I cd into others/ from /home/myname/ Here's the interesting part.
When I did a unix built-in pwd command, i get the ORIGINAL path name:-
%/home/others/
But when i echo the $PWD environment variable, i get the link path name:- %/home/myname/others/
Why is that so?
/var# ls -l lrwxrwxrwx 1 root root 10 Aug 22 13:21 mail -> spool/mail drwxr-xr-x 2 root root 4096 Jul 1 20:58 opt drwxr-xr-x 22 root root 4096 Dec 5 17:38 run drwxr-xr-x 12 root root 4096 Aug 22 13:21 spool drwxrwxrwt 14 root root 4096 Dec 6 02:46 tmp /var# cd mail /var/mail# echo $PWD /var/mail /var/mail# pwd /var/mail /var/mail# /bin/pwd /var/spool/mail
In other words, using $PWD is sufficient, because pwd might not give you better results (for any definition of better) anyway.
Why that is? /bin/pwd uses OS-specific calls to determine the current working directory - and in case of Linux, the kernel only keeps the resolved directory (see /proc/self/cwd), whereas the shell's pwds contain what the shell thinks it is in.