Tired of typing in that long directory name?

Sometimes when I am developing something I will end up working in two separate directories that are not that related. For example, I may be writing slides in my ~/class/cs421/periods/course-introduction/slides/ directory, and when they are done I want to put the PDF in ~/web/cs421/slides/.

You can save a lot of typing by creating some variables for it. So instead of

% cd ~/class/cs421/periods/course-introduction/slides/
% make slides.pdf
% cp slides.pdf ~/web/cs421/slides/introduction.pdf

you could have something like…

% slides=~/class/cs421/periods/course-introduction/slides/
% web=~/web/cs421/slides/
% cd $slides
% make slides.pdf
% cp slides.pdf $web/introduction.pdf

If you are going to use them a lot, you can put them in your startup file.

Another similiar trick is to use tab completion. I'm using zsh, which will run sub-shells if you hit tab. Suppose you are in that $slides directory as before, and you want to access the directory ~/class/cs421/periods/recursion/slides. Yeah, you could use ../.. but that can get tedious. But you could also type

cd $(pwd)

and hit <TAB> instead of <ENTER>. This will run the pwd command and paste it into your command line, leaving you with

cd ~/class/cs421/periods/course-introduction/slides/

You can then just edit the line to get what you want.

If you give cd two targets in zsh, it will treat that as a search and replace command for your current directory name. So

cd course-introduction recursion

will do the same directory switch as above.