Title : A few tips about the cd command Author: Solène Date : 04 September 2020 Tags : unix While everyone familiar with a shell know about the command `cd` there are a few tips you should know. ### Moving to your $HOME directory $ pwd /tmp $ cd $ pwd /home/solene Using `cd` without argument will change your current directory to your $HOME. ### Moving into someone $HOME directory While this should fail most of the time because people shouldn't allow anyone to visit their $HOME, there are use case it can be used though. $ cd ~user1 $ pwd /home/user1 $ cd ~solene $ pwd /home/solene Using `~user` as a parameter will move to that user $HOME directory, note that `cd` and `cd ~youruser` have the same result. ### Moving to previous directory This is a very useful command which allow going back and forth between two directories. $ pwd /home/solene $ cd /tmp $ pwd /tmp $ cd - /home/solene $ pwd /home/solene When you use `cd -` the command will move to the previous directory in which you were. There are two special variables in your shell: `PWD` and `OLDPWD`, when you move somewhere, `OLDPWD` will hold your current location before moving and then `PWD` hold the new path. When you use `cd -` the two variables get exchanged, this mean you can only jump from two paths using `cd -` multiple times. Please note that when using `cd -` your new location is displayed. ### Changing directory by modifying current PWD thfr@ showed me a cd feature I never heard about, and it's the perfect place to write about it. Note that this work in ksh and zsh but is reported to not work in bash. One example will explain better than any text. $ pwd /tmp/pobj/foobar-1.2.0/work $ cd 1.2.0 2.4.0 /tmp/pobj/foobar-2.4.0/work This tells `cd` to replace first parameter pattern by the second parameter in the current `PWD` and then cd into it. $ pwd /home/solene $ cd solene user1 /home/user1 This could be done in a bloated way with the following command: $ cd $(echo $PWD | sed "s/solene/user1/") I learned it a few minutes ago but I see a lot of uses cases where I could use it. ### Moving into the current directory after removal In some specific case, like having your shell into a directory that existed but was deleted and removed (this happens often when you working into compilation directories). A simple trick is to tell `cd` to go to the current location. $ cd . or $ cd $PWD And `cd` will go into the same path and you can start hacking again in that directory.