Using csh & tcsh

Creating Command Shortcuts

You probably have certain habits involving the commands you run. If so, you can save typing by using aliases—short names for often-used commands or command sequences. For instance, I use more and history a lot. By putting the following lines in my ˜/.cshrc file, I can run the commands more easily by typing m and h:

alias m more
alias h history

If you consider your own habits, you can probably think of some aliases that will help you enter commands more quickly. Suppose you often send files to your favorite printer with commands like these:

% pr file | lpr -Plwe
% pr -m list1 list2 | lpr -Plwe
% sort names | pr -5 | lpr -Plwe

An alias—let's call it print—allows you you do the same thing with less typing. Put this alias in your ˜/.cshrc file:

alias print 'pr \!* | lpr -Plwe'

Using the alias, you can type the previous set of printing commands like this:

% print file
% print -m list1 list2
% sort names | print -5

Notice that the definition of print is surrounded by quotes. That's because it contains special characters like | and !. The \!* in the definition expands to any specified arguments. (Arguments to an alias are normally tacked on to the end of the command the alias expands to. Using \!* allows you to place the arguments anywhere.)

Chapter 8, Using Aliases To Create Command Shortcuts, shows many more alias examples.