--- /dev/null
+The mg Tutorial
+---------------
+
+The mg editor is a public domain editor intended to loosely resemble GNU Emacs,
+while still retaining fast speed and a small memory footprint.
+
+Most mg commands involve using the Control (sometimes labelled "Ctrl") or the
+Meta (sometimes labelled "Alt") key. We will use the following conventions in
+this tutorial:
+
+ C-<chr> means hold down the Control key while typing the character <chr>.
+ M-<chr> means hold down the Meta key while typing the character <chr>.
+
+If you don't have a Meta key, you can use Esc instead. Press and release the
+Esc key and type <chr>. This is equivalent to M-<chr>.
+
+The first thing to learn is how to move up and down a document. To move your
+cursor down, use the down-arrow cursor key or C-n (Control and n).
+
+>> Now type C-n multiple times and move your cursor past this line.
+
+Congratulations. You have now learned how to move your cursor down. Note how
+mg has redrawn your screen so that the cursor is now in the middle of the
+screen. This is a feature of mg, which allows you to see the lines before and
+after the current cursor position.
+
+To move your cursor up, you can use the up-arrow cursor key or C-p (Control and
+p).
+
+>> Try using C-p and C-n to move up and down and then move past this line.
+
+The next commands to learn are how to move your cursor left and right. To do
+this, you can use the left-arrow and right-arrow cursor keys. Alternatively,
+you can use C-b and C-f to do this.
+
+>> Practise using the arrow keys or C-b and C-f on this line.
+
+To make it easy to remember these commands, it helps to remember by letter:
+P - Previous line, N - Next line, B - Backwards and F - Forward.
+
+Now that you've learned how to move single characters at a time, next we learn
+how to move one word at a time. To do this, you can use M-f (Meta and f) or
+M-b (Meta and b) to move forwards and backwards, one word at a time.
+
+>> Try moving one word at a time by using M-f and M-b on this line.
+
+Notice how the Ctrl and Meta key combinations perform related functions. C-f
+moves one letter forward, whereas M-f moves one word forward. There are many
+key combinations in mg, where C-<chr> will perform one function and M-<chr>
+will perform a similar related function.
+
+Next, we will learn how to refresh and redraw the screen.
+
+>> Now move the cursor down to this line and then type C-l (that's Control and
+ lowercase L) to refresh the screen.
+
+Note that C-l refreshes the screen and centers it on the line you typed it on.
+
+To move to the beginning or end of a line, you can use the Home and End keys,
+or you can use C-a and C-e to move to the beginning and end.
+
+>> Use C-a and C-e to move to the beginning and end of this line.
+
+The next commands we will learn is how to move up and down, one page at a time.
+To do this, you can use the Page Up (sometimes labelled PgUp) and Page Down
+(sometimes labelled PgDn) keys. You can also use C-v and M-v to do this. C-v
+moves the cursor down one page and M-v moves it up one page.
+
+>> Try using M-v and C-v to move up and down, one page at a time.
+
+The final two motion commands we will learn are M-< (Meta-Less than) and
+M-> (Meta-Greater than) which move you to the beginning and end of a file,
+respectively. You may not want to try that now as you will probably lose your
+place in this tutorial. Note that on most terminals, < is above the , key, so
+you'll need to press the Shift key to type <.
+
+Movement Summary
+-----------------
+
+The following is a summary of the movement commands we've learned so far:
+
+ C-f Move forward one character (can also use right arrow key).
+ C-b Move backward one character (can also use left arrow key).
+ C-p Move up one line (can also use up arrow key).
+ C-n Move down one line (can also use down arrow key).
+ M-f Move forward one word.
+ M-b Move backward one word.
+ C-a Move to beginning of line (can also use Home key).
+ C-e Move to end of line (can also use End key).
+ C-v Move forward one page (can also use PgDn/Page Down key).
+ M-v Move backward one page (can also use PgUp/Page Up key).
+ M-< Move to beginning of file.
+ M-> Move to end of file.
+
+Now that you've mastered the basics of moving around in mg, you can cause mg
+to execute these commands multiple times. The way to do this is to type C-u
+followed by some digits followed by a movement command.
+
+>> Type C-u 5 C-f to move forward 5 characters.
+
+In general, C-u allows you to execute any command multiple times, not just
+cursor motion commands. The only exception to this rule are C-v and M-v.
+When using these two commands with an argument, they move the cursor by that
+many lines instead of pages.
+
+Cancelling mg Commands
+----------------------
+
+If you have started typing out a command that you didn't mean to finish, you
+can use the C-g command to cancel the command immediately.
+
+>> For example, type C-u 50 and then type C-g to cancel the C-u command.
+>> Type Esc and then C-g to cancel the Esc key.
+
+In general, you can use C-g to stop any mg commands. You may type it multiple
+times if you wish. You should see the word "Quit" appear in the bottom of the
+screen when you type C-g indicating that a command was cancelled.
+
+In general, when in doubt, use C-g to get out of trouble.
+
+
+Inserting/Deleting Text
+-----------------------
+
+To insert text anywhere, simply move your cursor to the appropriate position
+and begin typing. To delete characters, use the backspace key. If you use
+M-<backspace> (Meta and backspace key), you will delete one word instead
+of one character at a time.
+
+To delete characters to the right of the cursor, you can use C-d to delete
+characters to the right of the current position. If you use M-d instead of
+C-d, you can delete one word at a time instead of one character at a time.
+
+>> Try inserting and deleting characters and words on this line.
+
+Note that if you type too many characters on a single line, the line will
+scroll off the screen and you will see a $ on the line to indicate that the
+line is too long to fit on the screen at one time.
+
+To delete a line at a time, you can use C-k to kill the line from the current
+cursor position to the end of the line. You can type C-k multiple times to
+kill many lines.
+
+You can issue insert or delete commands multiple times using C-u. For example,
+C-u 10 e will type out eeeeeeeeee, C-u 4 M-d will delete four words to the
+right of the cursor and so on.
+
+To undo any operation, you can use C-_ (That's control-underscore).
+
+Now if you kill something that you didn't mean to, you can yank it back from
+the dead by using C-y. In general, when you kill something bigger than a single
+character, mg saves it in a buffer somewhere and you can restore it by using
+C-y. This is useful for moving text around. You can kill text in one place,
+move your cursor to the new location and then use C-y to paste it there.
+
+Search for Text
+---------------
+
+To search for text, type C-s followed by the text you wish to search for. Note
+that as you start typing the characters, mg automatically searches as you type
+the characters.
+
+To continue searching the text you're looking for, type C-s to find the next
+instance. To search in reverse, type C-r instead of C-s. If you type C-s or
+C-r twice, it will simply search for the last text that you searched for.
+
+To stop searching for text, simply use the cursor keys (or C-f, C-b etc.) or
+C-g to stop the search operation.
+
+>> Use C-s foo to search for "foo" in the text. You can use C-s again to
+ find other instances of foo in the file.
+
+Note that if a word cannot be found, it will say Failing I-search: at the
+bottom of the screen. Typing C-s again will wrap the search around from the
+top of the file and begin searching from there.
+
+Replace Text
+------------
+
+To replace text, use M-%. You will be prompted for the text to search for and
+the text to replace it with. You will then be taken to the first instance of
+text from the current position. At this point you can do one of the following:
+
+ y - Replace the text at this instance and search for more items.
+ n - Skip this instance and search for more items.
+ . or Enter - Stop replacing text (You can also use C-g).
+ ! - Replace all the instances without prompting at each one.
+
+>> Try replacing "frobnitz" with "zutwalt" on this line.
+
+Cut/Copy/Paste Text
+-------------------
+
+As explained above, you can cut regions using C-k to kill multiple lines. To
+paste the text that you just cut, simply move your cursor to the point and
+then type C-y to restore the text. You may type C-y multiple times to restore
+the text. Hence, to copy text, you can use C-k to kill all the lines, use C-y
+to restore it immediately, then move to the region you want to copy it to and
+then type C-y again to restore the last cut text block again.
+
+Another way to cut or copy chunks of text is to first position your cursor at
+the starting point of the chunk of text. Then type C-<space> to mark this as
+the starting point to cut or copy. Then move the cursor to the end point of the
+text chunk that you wish to manipulate. Then type C-w to cut the region, or
+M-w to copy the region. If you wish to cancel marking a block of text, simply
+type C-g to cancel the operation.
+
+To paste the region that you've cut or copied above, simply move your cursor
+to the desired location and then type C-y to paste it.
+
+Status Line
+-----------
+
+At the bottom of your screen is a reverse highlighted line. This is the status
+line and lets you know some useful information about the file you're editing.
+
+On the status line, you should see "Mg: tutorial". This lets you know that
+you're editing a file named "tutorial". If you've edited this file and not
+saved it, it should have a "**" to the left of those words. If this file is
+read-only, you should see a "%%" to the left of those words.
+
+To the right of the status line, you should see L followed by digits and C
+followed by some more digits. These indicate the line number and column number
+of the file that your cursor is currently on. If you move the cursor around,
+you should see the line and column number change.
+
+In the middle of the screen, you should see the word "(fundamental)" which
+indicates that the current editing mode is "fundamental-mode". The mg editor
+also supports a c-mode that is more suited to editing C code. There are also
+some other useful editing modes for different situations. See the man page
+for mg(1) to learn about the various editing modes.
+
+Opening and Saving Files
+------------------------
+
+To open a file, you can use C-x C-f. You will then be prompted for a file name.
+If you type a file name that doesn't already exist, a new file will be opened
+for you. If the file name already exists, then it will be opened for you and
+you can begin editing it. Note that you do not need to type the whole file
+name for an existing file. You can type part of the file name and then press
+the TAB key. If there is only file name that matches, mg will fill in the rest
+of the file name for you. If there are multiple files, mg will display that
+the choice is ambiguous. If you type the TAB key again, mg will show you all
+the available choices for file names.
+
+NOTE: If you type C-x f instead of C-x C-f, you can use C-g to cancel the
+Set-Fill-Column command. You can also use C-g to cancel the C-x C-f command
+if you don't wish to open a new file.
+
+To save the file once you've edited it, use C-x C-s to save the file. When
+mg is done saving the file, you should see the words "Wrote /path/to/file"
+in the bottom of your screen. In general, it is a good idea to save quite
+often. When you save a file, mg saves a backup of the file with a tilde (~)
+character at the end.
+
+Windows
+-------
+
+The mg editor can support several windows at the same time, each one displaying
+different text. To split a screen into two horizontal windows use C-x 2 to do
+this. To return to one window, use C-x 1 to close the other windows and only
+keep the current window.
+
+>> Use C-x 2 to split the screen into two windows.
+
+>> Use C-x o to move from one window to the other. You can scroll up and down
+ in each window using the cursor keys or C-n and C-p keys.
+
+>> Use C-x 1 to restore back to one window.
+
+Buffers
+-------
+
+The mg editor is capable of editing multiple files at the same time. When you
+open a second file with C-x C-f, the first file is still being edited by mg.
+You can list all the buffers that are opened by mg by typing C-x C-b. The
+screen should divide into two and the top window will list the buffers that
+are currently open. Use C-x o to switch to the top window (we already learned
+this key combination above in the Windows section) and then use the arrow keys
+to move to the buffer you wish to switch to and then type the Enter key to
+select that buffer. Then use C-x 1 to switch back to only one window.
+
+You may also move back to the last opened buffer by using C-x b to toggle back
+and forth between two buffers. Note the difference between C-x b and C-x C-b.
+
+>> Use C-x C-f to open a new file
+>> Use C-x b to switch back and forth between that buffer and this one.
+
+To edit files in multiple windows, use C-x 2 to split the screen into two
+windows. Then use C-x C-f to open a new file in one of the two windows. You
+can then switch between the two windows using C-x o. You can switch between
+buffers in any window using C-x b. To go back to one window, use C-x 1.
+
+To kill any buffer, use C-x k. You will be prompted for the buffer to kill.
+By default, the current buffer is selected as the one to kill. You may also
+type another buffer name or use C-g to cancel the operation.
+
+Extended Commands
+-----------------
+
+The mg editor has several extended commands, more than what can be covered
+by the Control and Meta keys. The mg editor gets around this by using what is
+called the X (eXtend) command. There are two forms of this:
+
+ C-x Character eXtension. Followed by one character.
+ M-x Named character eXtension. Followed by a long command.
+
+You've already seen C-x C-f and C-x C-s to open and save a file. There are
+other longer commands. For instance, you can also open a file by typing
+M-x open-file Enter. When you type a command using M-x, mg prompts you for
+the command at the bottom of the screen. You can type out the whole command
+if you wish, or you can type out part of the command and then use the TAB key
+for autocompleting the command.
+
+For instance, to replace text, you can type M-x repl TAB enter to execute
+the replace-text command. To cancel this command, type C-g.
+
+To see a list of all available mg(1) commands, consult the man page.
+
+Exiting mg
+----------
+
+To exit mg temporarily and return to the shell, use C-z. This will take you
+back to the command shell. To return back to mg, type fg in the shell and you
+will be returned to your mg session.
+
+To exit mg permanently, type C-x C-c. If you have any unsaved buffers, you
+will be asked if you wish to save them or not.
+
+Conclusion
+----------
+
+This tutorial is meant to get new users up and running with mg. There is more
+information available via the mg(1) man page. If you have any suggestions for
+improvement, please don't hesitate to drop a message or (better still) submit
+a diff to tech@openbsd.org.
+
+Author Info
+-----------
+
+Original Author of this document: Mayukh Bose,
+Date last updated: 2012-05-25
+
+Copyright
+---------
+
+None. This document is in the public domain.
+
+
projects / pd_readline / blobdiff