Basic Editing¶

When you type characters into the editor, they are normally inserted into the file being edited (or appended to the file if the cursor is at the end of the file). This is the normal operating mode of the editor. If you want to replace some existing text, you have to delete the old text before or after you type in the replacement text. The Backspace key can be used for deleting text: move the cursor to right after the text you want to delete and hit Backspace a number of times.

Hit the Enter or Return key to insert a line break. For example, if the cursor was in the middle of a line and you hit Return, the line would be split into two lines with the cursor appearing at the beginning of the second line. Hit Backspace at the beginning of a line to eliminate a line break.

Use the arrow keys to move around the file. If your keyboard doesn't have arrow keys (or if they don't work for some reason), use ^F to move forwards (right), ^B to move backwards (left), ^P to move to the previous line (up), and ^N to move to the next line (down). The right and left arrow keys simply move forwards or backwards one character at a time through the text: if you're at the beginning of a line and you press left-arrow, you will end up at the end of the previous line. The up and down arrow keys move forwards and backwards by enough characters so that the cursor appears in the same column that it was in on the original line.

If you want to indent the text you enter, you can use the TAB key. This inserts a special control character which makes the characters which follow it begin at the next TAB STOP. TAB STOPS normally occur every 8 columns, but this can be changed with the ^T D command. Python programmers often set TAB STOPS on every 4 columns.

If for some reason your terminal screen gets messed up (for example, if you receive a mail notice from biff), you can have the editor refresh the screen by hitting ^R.

There are many other keys for deleting text and moving around the file. For example, hit ^D to delete the character the cursor is on instead of deleting backwards like Backspace. ^D will also delete a line break if the cursor is at the end of a line. Type ^Y to delete the entire line the cursor is on or ^J to delete just from the cursor to the end of the line.

Hit ^A to move the cursor to the beginning of the line it's on. Hit ^E to move the cursor to the end of the line. Hit ^U or ^V for scrolling the cursor up or down 1/2 a screen's worth. "Scrolling" means that the text on the screen moves, but the cursor stays at the same place relative to the screen. Hit ^K U or ^K V to move the cursor to the beginning or the end of the file. Look at the help screens in the editor to find even more delete and movement commands.

If you make a mistake, you can hit ^_ to "undo" it. On most keyboards you hit just ^- to get ^_, but on some you might have to hold both the Shift and Control keys down at the same time to get it. If you "undo" too much, you can "redo" the changes back into existence by hitting ^^ (type this with just ^6 on most keyboards).

If you were editing in one place within the file, and you then temporarily had to look or edit some other place within the file, you can get back to the original place by hitting ^K-. This command actually returns you to the last place you made a change in the file. You can step through a history of places with ^K- and ^K =, in the same way you can step through the history of changes with the "undo" and "redo" commands.

When you are done editing the file, hit ^K X to exit the editor. You will be prompted for a file name if you hadn't already named the file you were editing.

When you edit a file, you actually edit only a copy of the file. So if you decide that you don't want the changes you made to a file during a particular edit session, you can hit ^C to exit the editor without saving them.

If you edit a file and save the changes, a "backup" copy of that file is created in the current directory, with a ~ appended to the name, which contains the original version of the file.

Word wrap and formatting¶

If you type past the right edge of the screen in a C language or PASCAL file, the screen will scroll to the right to follow the cursor. If you type past the right edge of the screen in a normal file (one whose name doesn't end in .c, .h or .p), JOE will automatically wrap the last word onto the next line so that you don't have to hit Return. This is called word-wrap mode. Word-wrap can be turned on or off with the ^T W command. JOE's initialisation file is usually set up so that this mode is automatically turned on for all non-program files. See the section below on the joerc file to change this and other defaults.

Aside for Word-wrap mode, JOE does not automatically keep paragraphs formatted like some word processors. Instead, if you need a paragraph to be reformatted, hit ^K J. This command "fills in" the paragraph that the cursor is in, fitting as many words in a line as is possible. A paragraph, in this case, is a block of text separated above and below by a blank line or a line beginning with a period ("."). Lines can be indented by tab, any of the !#$%&)*+,-./:;=>?@\]^_|}~ characters or spaces.

The margins which JOE uses for paragraph formatting and word-wrap can be set with the ^T L and ^T R commands. If the left margin is set to a value other than 1, then when you start typing at the beginning of a line, the cursor will immediately jump to the left margin.

If you want to center a line within the margins, use the ^K A command.

Overtype mode¶

Sometimes it's tiresome to have to delete old text before or after you insert new text. This happens, for example, when you are changing a table and you want to maintain the column position of the right side of the table. When this occurs, you can put the editor in overtype mode with ^T T. When the editor is in this mode, the characters you type in replace existing characters, in the way an idealised typewriter would. Additionally, Backspace simply moves left instead of deleting the character to the left, when it's not at the end or beginning of a line. Overtype mode is not the natural way of dealing with text electronically, so you should go back to insert mode as soon as possible by typing ^T T again.

If you need to insert while you're in overtype mode, hit ^@. This inserts a single SPACE into the text.

Control and Meta characters¶

Each character is represented by a number. For example, the number for 'A' is 65 and the number for '1' is 49. All of the characters which you normally see have numbers in the range of 32 to 126 (this particular arbitrary assignment between characters and numbers is called the ASCII character set). The numbers outside of this range, from 0 to 255, aren't usually displayed, but sometimes have other special meanings. The number 10, for example, is used for the line breaks. You can enter these special, non-displayed control characters by first hitting ` and then hitting a character in the range @ A B C ... X Y Z [ ^ ] \ _ to get the number 0 to 31, and ? to get 127. For example, if you hit ` J, you'll insert a line break character, or if you hit ` I, you'll insert a TAB character (which does the same thing the TAB key does). A useful control character to enter is 12 (` L), which causes most printers to advance to the top of the page. You'll notice that JOE displays this character as an underlined L. You can enter the characters above 127, the meta characters, by first hitting ^\. This adds 128 to the next (possibly control) character entered. JOE displays characters above 128 in inverse video. Some foreign languages, which have more letters than English, use the meta characters for the rest of their alphabet. You have to put the editor in as-is mode (described later) to have these passed untranslated to the terminal.

Prompts¶

If you hit TAB at any file name prompt, joe will attempt to complete the name you entered as much as possible. If it couldn't complete the entire name, because there are more than one possible completions, joe beeps. If you hit TAB again, joe list the completions. You can use the arrow keys to move around this directory menu and press RETURN or SPACE to select an item. If you press the first letter of one of the directory entries, it will be selected, or if more than one entry has the same first letter, the cursor will jump between those entries. If you select a subdirectory or .., the directory name is appended to the prompt and the new directory is loaded into the menu. You can hit Backspace to go back to the previous directory.

Most prompts record a history of the responses you give them. You can hit up and down arrow to step through these histories.

Prompts are actually single line windows with no status line, so you can use any editing command that you normally use on text within the prompts. The prompt history is actually just other lines of the same "prompt file". Thus you can can search backwards though the prompt history with the normal ^K F command if you want.

Since prompts are windows, you can also switch out of them with ^K P and ^K N.

Where am I?¶

Hit ^K SPACE to have JOE report the line number, column number, and byte number on the last line of the screen. The number associated with the character the cursor is on (its ASCII code) is also shown. You can have the line number and/or column number always displayed on the status line by setting placing the appropriate escape sequences in the status line setup strings. Edit the joerc file for details.

File operations¶

You can hit ^K D to save the current file (possibly under a different name from what the file was called originally). After the file is saved, you can hit ^K E to edit a different file.

If you want to save only a selected section of the file, see the section on Blocks below.

If you want to include another file in the file you're editing, use ^K R to insert it.

Temporarily suspending the editor¶

If you need to temporarily stop the editor and go back to the shell, hit ^K Z. You might want to do this to stop whatever you're editing and answer an eMail message or read this man page, for example. You have to type fg or exit (you'll be told which when you hit ^K Z) to return to the editor.

Searching for text¶

Hit ^K F to have the editor search forwards or backwards for a text fragment (string) for you. You will be prompted for the text to search for. After you hit Return, you are prompted to enter options. You can just hit Return again to have the editor immediately search forwards for the text, or you can enter one or more of these options:

b

Search backwards instead of forwards.

i

Treat uppercase and lower case letters as the same when searching. Normally uppercase and lowercase letters are considered to be different.

nnn

(where nnn is a number) If you enter a number, JOE searches for the Nth occurrence of the text. This is useful for going to specific places in files structured in some regular manner.

r

Replace text. If you enter the r option, then you will be further prompted for replacement text. Each time the editor finds the search text, you will be prompted as to whether you want to replace the found search text with the replacement text. You hit: y to replace the text and then find the next occurrence, n to not replace this text, but to then find the next occurrence, l to replace the text and then stop searching, r to replace all of the remaining occurrences of the search text in the remainder of the file without asking for confirmation (subject to the nnn option above), or ^C to stop searching and replacing.

You can hit ^L to repeat the previous search.

Regular Expressions¶

A number of special character sequences may be entered as search text:

\*

This finds zero or more characters. For example, if you give A\*B as the search text, JOE will try to find an A followed by any number of characters and then a B.

\?

This finds exactly one character. For example, if you give A\?B as the search text, JOE will find AXB, but not AB or AXXB.

\^ \$

These match the beginning and end of a line. For example, if you give \^test\$, then JOE with find test on a line by itself.

\< \>

These match the beginning and end of a word. For example, if you give \<\*is\*\>, then joe will find whole words which have the substring is within them.

\[...]

This matches any single character which appears within the brackets. For example, if \[Tt]his is entered as the search string, then JOE finds both This and this. Ranges of characters can be entered within the brackets. For example, \[A-Z] finds any uppercase letter. If the first character given in the brackets is ^, then JOE tries to find any character not given in the the brackets.

\c

This works like \*, but matches a balanced C-language expression. For example, if you search for malloc(\c), then JOE will find all function calls to malloc, even if there was a ) within the parenthesis.

\+

This finds zero or more of the character which immediately follows the \+. For example, if you give \[ ]\+\[ ], where the characters within the brackets are both SPACE and TAB, then JOE will find whitespace.

\\

Matches a single \.

\n

This finds the special end-of-line or line-break character.

A number of special character sequences may also be given in the replacement string:

\&

This gets replaced by the text which matched the search string. For example, if the search string was \<\*\>, which matches words, and you give "\&", then joe will put quote marks around words.

\0 - \9

These get replaced with the text which matched the Nth \*, \?, \+, \c, \+, or \[...] in the search string.

\\

Use this if you need to put a \ in the replacement string.

\n

Use this if you need to put a line break in the replacement string.

Some examples:

Suppose you have a list of addresses, each on a separate line, which starts with "Address:" and has each element separated by commas. Like so:

Address: S. Holmes, 221b Baker St., London, England

If you wanted to rearrange the list, to get the country first, then the city, then the person's name, and then the address, you could do this:

Type ^K F to start the search, and type:

Address:\*,\*,\*,\*\$

to match "Address:", the four comma-separated elements, and then the end of the line. When asked for options, you would type r to replace the string, and then type:

Address:\3,\2,\0,\1

To shuffle the information the way you want it. After hitting return, the search would begin, and the sample line would be changed to:

Address: England, London, S. Holmes, 221b Baker St.

Blocks¶

If you want to move, copy, save or delete a specific section of text, you can do it with highlighted blocks. First, move the cursor to the start of the section of text you want to work on, and press ^K B. Then move the cursor to the character just after the end of the text you want to affect and press ^K K. The text between the ^K B and ^K K should become highlighted. Now you can move your cursor to someplace else in your document and press ^K M to move the highlighted text there. You can press ^K C to make a copy of the highlighted text and insert it to where the cursor is positioned. ^K Y to deletes the highlighted text. ^K W, writes the highlighted text to a file.

A very useful command is ^K /, which filters a block of text through a unix command. For example, if you select a list of words with ^K B and ^K K, and then type ^K / sort, the list of words will be sorted. Another useful unix command for ^K /, is tr. If you type ^K / tr a-z A-Z, then all of the letters in the highlighted block will be converted to uppercase.

After you are finished with some block operations, you can just leave the highlighting on if you don't mind it (of course, if you accidentally hit ^K Y without noticing...). If it really bothers you, however, just hit ^K B ^K K, to turn the highlighting off.

Indenting program blocks¶

Auto-indent mode toggled with the ^T I command. The joerc is normally set up so that files with names ending with .p, .c or .h have auto-indent mode enabled. When auto-indent mode is enabled and you hit Return, the cursor will be placed in the same column that the first non-SPACE/TAB character was in on the original line.

You can use the ^K , and ^K . commands to shift a block of text to the left or right. If no highlighting is set when you give these commands, the program block the cursor is located in will be selected, and will be moved by subsequent ^K , and ^K . commands. The number of columns these commands shift by can be set through a ^T option.

Windows¶

You can edit more than one file at the same time or edit two or more different places of the same file. To do this, hit ^K O, to split the screen into two windows. Use ^K P or ^K N to move the cursor into the top window or the lower window. Use ^K E to edit a new file in one of the windows. A window will go away when you save the file with ^K X or abort the file with ^C. If you abort a file which exists in two windows, one of the window goes away, not the file.

You can hit ^K O within a window to create even more windows. If you have too many windows on the screen, but you don't want to eliminate them, you can hit ^K I. This will show only the window the cursor is in, or if there was only one window on the screen to begin with, try to fit all hidden windows on the screen. If there are more windows than can fit on the screen, you can hit ^K N on the bottom-most window or ^K P on the top-most window to get to them.

If you gave more than one file name to JOE on the command line, each file will be placed in a different window.

You can change the height of the windows with the ^K G and ^K T commands.

Keyboard macros¶

Macros allow you to record a series of keystrokes and replay them with the press of two keys. This is useful to automate repetitive tasks. To start a macro recording, hit ^K [ followed by a number from 0 to 9. The status line will display (Macro n recording...). Now, type in the series of keystrokes that you want to be able to repeat. The commands you type will have their usual effect. Hit ^K ] to stop recording the macro. Hit ^K followed by the number you recorded the macro in to execute one iteration of the keystrokes.

For example, if you want to put "**" in front of a number of lines, you can type:

^K [ ^A ** <down arrow> ^K ]

Which starts the macro recording, moves the cursor to the beginning of the line, inserts "**", moves the cursor down one line, and then ends the recording. Since we included the keystrokes needed to position the cursor on the next line, we can repeatedly use this macro without having to move the cursor ourselves, something you should always keep in mind when recording a macro.

If you find that the macro you are recording itself has a repeated set of keystrokes in it, you can record a macro within the macro, as long as you use a different macro number. Also you can execute previously recorded macros from within new macros.

Repeat¶

You can use the repeat command, ^K \, to repeat a macro, or any other edit command or even a normal character, a specified number of times. Hit ^K \, type in the number of times you want the command repeated and press Return. The next edit command you now give will be repeated that many times.

For example, to delete the next 20 lines of text, type:

^K  20<return>^Y

Rectangle mode¶

Type ^T X to have ^K B and ^K K select rectangular blocks instead of stream-of-text blocks. This mode is useful for moving, copying, deleting or saving columns of text. You can also filter columns of text with the ^K / command — if you want to sort a column, for example. The insert file command, ^K R is also effected.

When rectangle mode is selected, overtype mode (^T T) is also useful. When overtype mode is selected, rectangles will replace existing text instead of getting inserted before it. Also the delete block command (^K Y) will clear the selected rectangle with SPACEs and TABs instead of deleting it. Overtype mode is especially useful for the filter block command (^K /), since it will maintain the original width of the selected column.

Tag search¶

If you are editing a large C program with many source files, you can use the ctags program to generate a tags file. This file contains a list of program symbols and the files and positions where the symbols are defined. The ^K ; command can be used to lookup a symbol (functions, defined constants, etc.), load the file where the symbol is defined into the current window and position the cursor to where the symbol is defined. ^K ; prompts you for the symbol you want, but uses the symbol the cursor was on as a default. Since ^K ; loads the definition file into the current window, you probably want to split the window first with ^K O, to have both the original file and the definition file loaded.

Shell windows¶

Hit ^K ' to run a command shell in one of JOE's windows. When the cursor is at the end of a shell window (use ^K V if it's not), whatever you type is passed to the shell instead of the window. Any output from the shell or from commands executed in the shell is appended to the shell window (the cursor will follow this output if it's at the end of the shell window). This command is useful for recording the results of shell commands — for example the output of make, the result of grepping a set of files for a string, or directory listings from FTP sessions. Besides typeable characters, the keys ^C, Backspace, DEL, Return and ^D are passed to the shell. Type the shell exit command to stop recording shell output. If you press ^C in a shell window, when the cursor is not at the end of the window, the shell is killed.