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2. The Command Line environment.

If you only use Windows or Mac, pay attention here. These applications operate ONLY in a Command Line enviroment. I will list the Unix command and it's Dos equivalent, where applicable, along with a brief explanation of the command operation.

2.1 Using the keyboard - Special Keystrokes

Whenever you see a character prefaced with the letters "ctrl-", that means "hold down the ctrl key" and press the key that follows.

"ctrl-z" means "hold down the ctrl key and press z

2.2 The four arrow keys

on the right side of the keyboard are used to edit the command line.
                            |  /\  |
                            |  Up  |
                      ------ ------ -------
                     | Left | Down | Right |
                     |  <-  |  \/  |   ->  |
                      ------ ------ -------
The UP and DOWN arrow keys are used to scroll through the previous commands that have been on the command line. Once a particular command is selected, the LEFT and RIGHT arrow keys scroll sideways back and forth on the command, positioning the cursor where characters may be deleteded with the BACKSPACE or DELETE keys.

2.3 The Backspace and Delete keys

both delete the character to the left of the cursor. In some VT100 simulations (your telnet terminal emulation), the BACKSPACE key does not function correctly. The DELETE almost always functions correctly.

2.4 "ctrl-z" Suspend Task Key

At any time in most tasks, you can type


to suspend or bail out of the task you are currently running. Once suspended, the ps and kill commands (explained later) can be used to terminate the job. The fg command can be used to re-activate the task.

2.5 tab key - Automatic file name completion

The tab key used after any command will automatically complete a file or directory name if it is unique or complete the first unique letters. Hitting the tab key twice will list the directory.

Directory contents:     Ip-Dev-1.html  Ip-Dev-3.html  Ip-Dev.html
                        Ip-Dev-2.html  Ip-Dev-4.html  Ip-Dev.sgml

type    less I          followed by tab, will extend the command line to:
        less Ip-Dev     typing two tabs will list the directory.
                        typing ".s" tab will extend the command line to:
        less Ip-Dev.sgml

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