Unix Commands

General Format

Unix commands discussed in this section work on both the Hercules computer and the Linux systems. Unix commands are cryptic, often only two or three characters in length. However, they are representative of the function they perform. For example, ls is the command to get a directory listing.

The general format for Unix commands is:
        command -options other arguments

where "command" is the name of some command followed by a number of options or other arguments.
Options are generally single characters that represent specific options. The minus sign "-" should be entered before an option.
        Type in ls 
        and then type in ls -l

Notice that the "-l" option results in a 'long' listing showing file permissions.

List of Commands

A Unix command summary is stored in HTML form on the CS Department's WWW site at:

Please be aware that you are responsible for learning all of these basic commands.

Here is a very helpful UNIX Tutorial.

Finding Unix Commands

Unix commands descriptions are all kept on-line in the form of "manual" entries. If you do not know the specific command to perform a function, you can enter the "man " command, followed by the "-k" option, and then a keyword that relates to the command you are looking for.  For example, if you wanted to find the command to change your password, you could use "password" as a keyword.
Type in the following:
man -k password 

There will be several related Unix manual entries cited. Look for the one most relevant to what you want to do. i.e.
 change login password and password attributes 

What is the 5 letter Unix command to change your password?
This document will present other Unix commands in the context of tasks that you will need to perform for your CS115 class. It is assumed that you have no prior experience with Unix and are using your Hercules account for the first time.