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Arrange for what is called a "shell account" on some Unix system. Most Internet Service Providers (ISPs) can provide this service. Use the terminal emulator program and a modem to dial in. Learn the basic Unix commands. If the system has Emacs installed, or you can persuade the system administrator to install it, this is your second chance to learn it. It is probably best to learn it at this point, because administering a Unix system (the next stage) will call for you to edit files. Therefore, I include here my suggestions for learning both Unix and Emacs.
When you arrange for a shell account, or set up a new account on your own machine, you will have to decide on a username and a password. Your username will also be used in your email address, so try to find something short and memorable. Your password is important, and should be hard to guess. That usually means at least six characters, including at least one non-alphanumeric character.
When a Unix system is ready for you to log in, it normally displays a prompt ending with "login:". At this point you should type in your username. It will then prompt you for your password, and will turn off command echoing while you type it in.
The command to finish a terminal session is
There are many kinds of documentation available on a Linux system.
Traditionally, each command has a manual page which can be
displayed by the
The numbers in parentheses are sections of the manual. User commands are in section 1. Functions called from within programs are in sections 2 and 3. Commands used mostly by the system administrator are in section 8. You can find out more about the on-line manual with the command
The program that interprets your command is a "shell". Under DOS,
COMMAND.COM is the shell. Most Unix shells are descendents of either
the Bourne shell
Many Linux programs from the Free Software Foundation are best
documented in info pages. For example, the C compiler documentation
can be displayed by typing
Under Unix, commands normally accept options starting with a minus sign rather than the forward slash used under DOS. In a path, directory names are separated by forward slashes rather than backward slashes. Both operating systems have a "standard input", by default the keyboard, and a "standard output", by default the display screen. You can redirect the standard input using "<", and redirect the output using ">". You can use the output from one command as the input of another by separating the two commands with "|". This is called the "pipe" symbol.
If a program gets "stuck", here is a sequence of keystrokes to try:
You can find general Unix information, including manual pages for several systems at http://www.cis.ohio-state.edu/hypertext/man_pages.html
There is a tutorial entitled "Beginning Unix and the C Shell" at http://www.eng.hawaii.edu:80/Courses/C.unix/page-03.html.
You can get general help from http://www.nova.edu/Inter-Links/UNIXhelp/TOP_.html or http://www.eecs.nwu.edu/unix.html
You can find a list of books on UNIX at http://www.eskimo.com/~cher/eskimospace/booklist.html.
When you start Emacs, you will normally list on the command line one
or more files which you will be editing. To edit a file named
"foobar" with Emacs, you would enter the command
Type C-h for help; (`C-' means use CTRL key.) Type C-x u to undo changes. Type C-h t for a tutorial on using Emacs. Type C-h i to enter Info, which you can use to read GNU documentation. To kill the Emacs job, type C-x C-c.
Note the way Emacs documentation refers to key combinations. C-h means hold the control key down while typing "h". You will also run into key combinations like M-v, which is pronounced "meta v". The tutorial suggests holding down the key labeled "edit" or "meta" then typing "v". I have never run across a keyboard with those keys, so I always use the escape key instead: typing "Esc" then "v" (two separate keystrokes). After using Emacs for a long time, I discovered that under Linux, the left "Alt" key works like a "meta" key. You may want to use this. On the other hand, some of these key combinations may conflict with your screen reader or communications program under DOS. Using the escape key is more reliable.
Three of the above commands start with C-h, which may be treated as a backspace by your communications program. In that case, you may access the help command using the long form M-x help. Conversely, you may find that pressing the backspace key starts the help command. This issue is treated in the Emacs FAQ, which is available within Emacs using C-h F or M-x help F. Look for the question "Why does the `Backspace' key invoke help?". In the mean time, you can end the help session with the command C-g. (This is the keyboard-quit command, which cancels any prefix keys you have typed.)
You may also find that C-s and C-q are unavailable because they are used for flow control (XON and XOFF). You should look at the question "How do I handle C-s and C-q being used for flow control?" in the FAQ. For the particular command C-x C-s (save buffer), you may substitute the command C-x s (save-some-buffers). The former command saves the current buffer, while the latter asks the user about each of the modified buffers.
Note in particular the command "C-h t" to start the Emacs tutorial. That is one the first things you will want to try. I will only make a couple of comments on the tutorial. To move the cursor, it gives the four commands C-f, C-b, C-p, and C-n (for forward, back, previous line, and next line). These commands always work. However, with a properly installed Emacs, the regular arrow keys should also work. Try them out and use them if you are more comfortable with them. Similarly, you may be able to use home, end, page down, and page up keys in place of the standard commands C-a, C-e, C-v, and M-v. Finally, all Emacspeak commands begin with C-e. Once you start using Emacspeak, you will have to type it twice to get the end of line function. (The "End" key should be unaffected by Emacspeak.)
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