Using csh & tcsh

Chapter 8. Using Aliases To Create Command Shortcuts

In This chapter:

• Defining Aliases

• Uses for Aliases

• Using Sets of Aliases

As you use the shell, you'll notice patterns in the way you work. Once you do, you can save typing by using the shell's aliasing mechanism to create short alternate names for frequently used commands or command sequences. This chapter discusses how to define and remove aliases, ways in which aliases are useful, and how to manage multiple sets of aliases.

Defining Aliases

An alias definition has the following form:

alias name definition

name is what you want to call the alias, and definition is the command to run when you use name as a command. For example, the following aliases allow you to use h and m as short names for the history and more commands:

alias h history
alias m more

Aliases are best placed in your ˜/.cshrc file so that they're available to your login shell as well as any subshells. However, don't put an alias in ˜/.cshrc until you've verified that it works correctly. First, define the alias at the command line, and then test it:

% alias h history                 Define the alias
% h                               Try it out

If an alias doesn't work as you expect, use one of the following commands to determine how the shell is interpreting your definition:

% alias name                        Show definition for alias name
% alias                             Show definitions for all aliases

To get rid of an alias, use unalias:

% unalias name                      Remove alias name
% unalias *                         Remove all aliases

unalias is especially useful when you're testing an alias at the command ...