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.