How to Use CDPATH to define the base directory for cd command

Use CDPATH to define the base directory for
cd command

If you are frequently performing cd to subdirectories of a specific parent
directory, you can set the CDPATH to the parent directory and perform cd to
the subdirectories without giving the parent directory path as explained
below.

[ramesh@dev-db ~]# pwd
/home/ramesh
[ramesh@dev-db ~]# cd mail
-bash: cd: mail: No such file or directory
[Note: This is looking for mail directory under current
directory]
[ramesh@dev-db ~]# export CDPATH=/etc
[ramesh@dev-db ~]# cd mail
/etc/mail
[Note: This is looking for mail under /etc and not
under current directory]
[ramesh@dev-db /etc/mail]# pwd
/etc/mail
To make this change permanent, add export CDPATH=/etc to your
~/.bash_profile

Similar to the PATH variable, you can add more than one directory entry in
the CDPATH variable, separating them with : , as shown below.
export CDPATH=.:~:/etc:/var
This hack can be very helpful under the following situations:
o Oracle DBAs frequently working under $ORACLE_HOME, can set
 the CDPATH variable to the oracle home
o Unix sysadmins frequently working under /etc, can set the
 CDPATH variable to /etc
o Developers frequently working under project directory
 /home/projects, can set the CDPATH variable to /home/projects
o End-users frequently accessing the subdirectories under their
 home directory, can set the CDPATH variable to ~ (home
directory)