The Logout Process

You have completed working in your Unix session and now want to log out. Whether graphically or text-based, you should consider a few things before you do. Logging out is also a fairly simple process. There are a few important things to consider when logging out. First, before logging out, always remember that Unix is a multiuser platform that could be serving hundreds of clients at one time. Make sure that you consider these users as well. When you log in, you identify yourself to the system. Therefore, Unix knows about any files you open. Unix knows when you decide to log out; if you forget something such as a program you may have left running during the logout process, Unix will close it for you because it has tracked your activity. This is one example of the power of Unix.

Another concern is security. To remain logged in to Unix all the time is also a security risk. You should always remember to log out whenever you are done with a session. Here is one example of how forgetting to log out can hurt you. Imagine being at work and logging in to a system in the morning and leaving at the end of the day and you forget to log out. Consider that someone else could wander along and now change things in the system "as you," because he or she would be logged in with your credentials. Remember that credentials are your username and password, which usually tie to an account on the system with your personal information associated with it. Now, things were changed, you don't know what was changed, even if you say it wasn't you, it was your account. This could lead to significant problems, so better to be safe than sorry. In short, learn to log out and understand the importance of it.

Logging out of a Unix system is fairly easy. Let's take a look at how to do it using both text-based and graphical methods.

Text-Based Logout

When working within the shell prompt, all you need to do to log out is type "logout." The command would be seen as

 >logout 

Once you issue the logout command, the Unix system will immediately return to a login prompt. You have just successfully logged in and out of a Unix system. If it was your first time, you should be proud of yourselfthis was quite an accomplishment. If you have done this once or twice before, continue to practice, because practice makes perfect and this is one task you will master in no time. Remember, you must log in to a Unix system to work within it. Also remember that even though this may have been a somewhat easy task, there were many things to consider, mainly your environment, your security, and your data integrity. One last thing to mention about logging out would be to consider the many different distributions of Unix available today. Some distros may not accept the logout command. Some expect other commands such as exit. A common error message of "Not login shell" may indicate the need for the exit command.

Graphical Logout

When logging out of your Unix system graphically, you will need to take more steps than when logging out using the text-based method. When logging out of a text-based session, you simply need to issue the command. Within a graphical environment, you need to manipulate the graphical environment itself to log out. The icon you see that indicates the main menu in which the logout process is initiated from may vary depending on your Unix distribution, but in most all cases, the first icon (sometimes represented as a K or the SuSE logo), which produces the Logout… command from menu. Once selected, you will be given an option to end your session, turn off your computer, restart your computer (warm start), or simply cancel your logout and go back to your current session.

A House with No Mouse Don't forget your keyboard shortcuts such as the Tab key. Remember that not all systems come with a mouse, but all require a keyboard. This is determined by systems BIOS upon startup. You will always have a keyboard to work from, so you should really consider practicing logging in and out of your Unix system without the use of your mouse as much as possible. It's not common to find mice on Unix systems.