This manual is for Eat (version 0.9.4, 15 December 2023), a terminal emulator for Emacs.
Copyright © 2022, 2023 Akib Azmain Turja.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.
Next: Hello Terminal, Up: Eat Manual [Contents][Index]
Eat (Emulate A Terminal) is a terminal emulator for Emacs. It emulates a XTerm-like terminal, just like many other terminal emulators. But it has some key features that make Eat distinct from other terminal emulators.
Firstly, it’s in Emacs, which means you don’t need to leave the comfort of Emacs to use terminal.
Secondly, it’s easy and convenient to use. It is tries to stay out of your way, allowing you to maximize your productivity.
Finally, special care has been taken while designing the keybindings, so that the terminal doesn’t conflict with Emacs default keybindings on both graphical display and text display, while still allowing you to run full screen programs like Emacs within the terminal.
Next: Project-local Terminal, Previous: Introduction, Up: Eat Manual [Contents][Index]
The terminal can be started with M-x eat. It’ll create a terminal and run the default shell (see Interactive Shell in GNU Emacs Manual) in it. You should get a shell prompt and be able to write shell commands and execute them. Full screen programs like ‘htop’, ‘lynx’ and Emacs will work inside it, just like any other terminal. (If the terminal doesn’t work as expected, see Common Problems.)
If an Eat terminal already exists, M-x eat will switch to it. To create a new terminal, call it with a prefix argument like this, C-u M-x eat.
If you give it a numeric prefix argument N, for example C-u 42 M-x eat, it’ll switch to a terminal in the buffer *eat*<N>, *eat*<42> for example, or it’ll create a new terminal if that buffer doesn’t exist.
If you give it double prefix argument, for example C-u C-u M-x eat, you’ll be prompted for the program or shell command to run, and it’ll be run in a newly created terminal.
Next: Eshell Terminal Emulation, Previous: Hello Terminal, Up: Eat Manual [Contents][Index]
Usually, you don’t use a single terminal for everything, instead you
open a terminal for each project that needs it. So there is command
named eat-project. It opens a new terminal in project root
directory, or switches to a already existing project terminal. It too
accepts prefix argument, just like the ordinary eat command.
Next: Keyboard, Previous: Project-local Terminal, Up: Eat Manual [Contents][Index]
Eat also supports terminal emulation outside Eat’s terminal. So you can emulate terminal in Eshell (see Eshell manual) with Eat. After configuring Eshell to use Eat for terminal emulation, you can run any full screen terminal program in Eshell.
To enable terminal emulation in Eshell, enable the global minor mode
eat-eshell-mode. It will enable Eat’s terminal emulation in
Eshell. To disable the terminal emulation, disable the minor mode.
You can’t toggle the global minor mode while any Eshell command is running, so terminate any Eshell command or wait them to finish before toggling the mode.
Unless stated otherwise, everything described in this manual about Eat terminal also applies to Eshell terminal emulation.
You might also want to set eshell-visual-commands user option
to nil, since they’ll work in Eshell when eat-eshell-mode is
enabled.
If you want to run Eshell visual commands with Eat, you can enable the
global minor mode eat-eshell-visual-command-mode.
Next: Mouse, Previous: Eshell Terminal Emulation, Up: Eat Manual [Contents][Index]
Just like any other text terminal, the primary interaction device with Eat terminal is the keyboard. Eat forwards all supported keyboard events like a, E, RET, C-a to the terminal.
However, this conflict with Emacs keybinding conventions, and makes it almost impossible to call any other Emacs command. So, by default, Eat doesn’t intercept the key sequences beginning with the following keys and lets Emacs to handle them: C-\, C-c, C-x, C-g, C-h, C-M-c, C-u, C-q, M-x, M-:, M-! and M-&.
To input the above key sequences, prefix them with C-q. C-q reads the next event and sends to directly to the terminal. For example, to input M-:, use the key sequence C-q M-:.
For an alternative way to input these exceptional characters, see Char Mode.
Next: Input Modes, Previous: Keyboard, Up: Eat Manual [Contents][Index]
Eat supports mouse tracking. That means in programs like Emacs, ‘htop’, etc, that support mouse, you can hover and click on text and buttons. You can also use your mouse wheel to scroll text, if the program supports it.
See Mouse Tracking to configure mouse tracking.
Next: Password Input, Previous: Mouse, Up: Eat Manual [Contents][Index]
By default, Eat forwards all supported keys to terminals, except some exceptions. It is possible to input them with C-q, but it is not very convenient.
To conveniently input those character, they should be bound to input themselves to the terminal (i.e. pressing M-x will input M-x, bypassing Emacs). But this is conflicts with Emacs’s default keybindings, so this can’t done, at least by default.
To overcome the problem, Eat implements several “input modes”. Each input mode has a different set of keybindings for different applications.
“Semi-char mode” is the default input mode of Eat. This works for most inputs. It forwards all keys, except C-\, C-c, C-x, C-g, C-h, C-M-c, C-u, M-x, C-q, M-:, M-!, M-& and some other keys, Emacs handles them.
To input these exceptions, there is a key C-q. This reads the next input event and sends that as the input. For example, the key sequences C-q M-: inputs M-:, C-q C-g inputs C-g.
Input methods (see Input Methods in GNU Emacs Manual) work in this mode, so, unlike Term (see Emacs Terminal Emulator in GNU Emacs Manual), Emacs built-in terminal emulator, you can still input any character.
In “semi-char mode”, C-c C-c sends a C-c, just for convenience, and C-c C-k kills the terminal program.
You can customize the exceptions by customizing the user option
eat-semi-char-non-bound-keys, and
eat-eshell-semi-char-non-bound-keys for Eshell integration.
Both user options contain a list of keys of form [key],
where key is a key not to bind. key mustn’t contain meta
modifier. To not bind a key with meta modifier, use a vector of form
[?\e key], where key is the key without meta
modifier. These user options contain all the “semi-char” mode
exceptions listed above, plus some more exceptions.
If you set the user options manually (for example, with setq),
you must call eat-update-semi-char-mode-map or
eat-eshell-update-semi-char-mode-map respectively, and finally
reload Eat (you can do this with the command eat-reload).
Or alternatively you can set the user options before Eat is loaded.
By default, Eat is in “semi-char mode”. In this input mode, Eat forwards all supported keys to terminals, except some exceptions, see Semi-char Mode. It is possible to input them with C-q, but it is not very convenient.
To overcome this problem, Eat implements another input mode called
“char mode”. To switch to “char mode”, press C-c M-d in
“semi-char mode”. In Eshell, the command
eshell-toggle-direct-send is remapped to enable
“char-mode”, which is usually bound to C-c M-d.
In this input mode, Eat forwards all supported keys. However, input methods still work in this mode, so you can still input keys that are not on your keyboard.
To get out of “char mode”, press C-M-m or M-RET, this switches back to “semi-char mode”.
In “emacs mode”, no input events are send to the terminal. In this mode, you can interact with the terminal buffer just like a regular buffer. However, you are not allowed to change the buffer contents.
To switch to “emacs mode”, press C-c C-e from “semi-char mode”.
In this mode, C-c C-k kills the terminal program like in “semi-char mode”.
From “emacs mode”, you can switch to “semi-char mode” with
C-c C-j and to “char mode” with C-c M-d. In Eshell, the
command eshell-toggle-direct-send is remapped to enable
“char-mode”, which is usually bound to C-c M-d.
In “line mode”, input is sent one line at a line, similar to Comint or Shell mode (see Interactive Shell in GNU Emacs Manual). Like “emacs mode”, you can interact with buffer as you wish; but at the very end of the buffer, you can edit the input line with usual Emacs commands. This is not available in Eshell.
To enter “line mode”, press C-c C-l from “semi-char mode” or “emacs mode”.
RET sends the current input with a trailing newline, and clear the input area for new input to be written. When called with a prefix argument, no newline is appended before sending input. To input a newline character without actually sending it, you can press C-c SPC.
C-c C-c discards the input completely and sends an interrupt to the terminal. C-d deletes the character after the point, or sends EOF if the input is empty.
You can’t modify the terminal in “line mode”, you can write only in
the input line. Eat automatically moves the point to the input line
if you try to insert character in the terminal region. This behavior
can be disabled by customizing eat-line-auto-move-to-input to
nil.
You can exit to “emacs mode”, “semi-char mode” or “char mode” with C-c C-e, C-c C-j or C-c M-d respectively. If there’s any pending input when exiting line mode, it is sent as is to the terminal.
The input history is recorded. You can cycle through the history with M-p and M-n, and also with C-up and C-down. C-c M-r and C-c M-s searches the input history taking the current input as the query. C-c M-r searches backward while C-c M-s searches forward. And C-c C-r searches the input history using minibuffer with completion, useful specially if you use any minibuffer completion UI/framework.
You can also use Isearch
(see Incremental Search in GNU Emacs Manual) to search
through the input history, with M-r. You can also customize
eat-line-input-history-isearch to use all standard Isearch
commands to search the input history.
Controls where Isearch searches in Eat buffer. If t, usual
Isearch commands in Eat buffer search in the input history. If
dwim, Isearch keys search in the input history only when
initial point position is on input line. When starting Isearch from
other parts of the Eat buffer, they search in the Eat buffer. If
nil, Isearch operates on the whole Eat buffer.
Input history is not loaded from the shell history file, to do that, See Line Mode Integration.
Next: Shell Integration, Previous: Input Modes, Up: Eat Manual [Contents][Index]
By default, every keystroke gets recorded in the lossage, which can be seen by pressing C-h l. This is actually a good thing, unless you’re inputting password.
Emacs doesn’t record keystrokes when a password is read from the
minibuffer. However, when the password prompt is in the terminal, the
keys you use to type in your password gets recorded. To prevent this
from happening, you can use the command eat-send-command,
it’ll read password from the minibuffer and send it. Since the
password is read from the minibuffer, it’s not recorded.
Next: Querying Before Kill, Previous: Password Input, Up: Eat Manual [Contents][Index]
Eat comes with shell scripts to integrate your favorite shell with Eat. When shell integration is enabled and the script is loaded in your shell, it’ll take care of everything and provide many useful features.
Currently only GNU Bash and Zsh are supported.
If you use GNU Bash, put the following in your ‘.bashrc’ file:
[ -n "$EAT_SHELL_INTEGRATION_DIR" ] && \ source "$EAT_SHELL_INTEGRATION_DIR/bash"
If you use Zsh, put the following in your ‘.zshrc’ file:
[ -n "$EAT_SHELL_INTEGRATION_DIR" ] && \ source "$EAT_SHELL_INTEGRATION_DIR/zsh"
After you’ve setup shell integration, the Eat will track the working
directory of your shell. That means find-file will start
from your shell’s current working directory. This also works in
Eshell, but after the program exits, the current working directory is
changed back to the directory from where the program was invoked.
This controls directory tracking. When set to non-nil, Eat
tracks the current working directory of programs.
When shell integration is setup, Eat annotates each shell prompt. Eat puts a mark on the shell prompt indicating the whether the command entered in that prompt is running, exited successfully or exited with non-zero status. This doesn’t work in Eshell. You can disable this feature if you want.
This controls shell prompt annotation by Eat. When set to
non-nil, Eat annotates shell prompts to indicate the status of
the command entered in that prompt.
Eat uses the marginal area (see Display Margins in GNU Emacs Lisp Reference Manual) on the left side to display the annotation. You also use the right margin.
This controls where the shell prompt annotations are displayed. When
set to left-margin (the default), Eat uses the left margin.
When set to right-margin, Eat uses the right margin.
Eat uses the strings “-”, “0” and “X” respectively to indicate
the command is running, the command has succeeded and the command has
failed. You can also customize the them. The user option
eat-shell-prompt-annotation-running-margin-indicator and the
face eat-shell-prompt-annotation-running control the indicator
used to indicate the command is running. The user option
eat-shell-prompt-annotation-success-margin-indicator and the
face eat-shell-prompt-annotation-success control the indicator
used to indicate the command has exited successfully. And finally
the user option
eat-shell-prompt-annotation-failure-margin-indicator and the
face eat-shell-prompt-annotation-failure control the indicator
used to indicate the command has exited unsuccessfully with non-zero
exit status.
After enabling shell integration, you can send messages to Emacs from your shell. Then you can handle the message on Emacs side using usual Emacs Lisp function.
When shell integration script is loaded, a function named
_eat_msg is defined in your shell. You can use this to send
any message to Emacs. (The ‘_’ in the beginning of the function
name is intentional to prevent shadowing any actual command.)
Send message message, handled by the handler named handler-name in Emacs.
The messages are handled with the handlers defined in
eat-message-handler-alist.
Alist of message handler name and its handler function. The keys are
the names of message handlers (i.e. the handler-name argument of
_eat_msg), and the values are their respective handler
functions. The handler function is called with the message
arguments of _eat_msg. Messages with undefined handlers are
ignored. To disable message passing, set this to nil.
Beware, messages can be sent by malicious and/or buggy programs running in the shell, therefore you should always verify the message before doing anywhere.
When shell integration is enabled, the input history of line mode is automatically filled with the shell history when the shell starts. Also you can make Eat automatically switch to “line mode” (see Line Mode) for you when the shell prompt appears.
When non-nil, automatically switch to line mode the shell prompt appears.
Next: Display, Previous: Shell Integration, Up: Eat Manual [Contents][Index]
When a terminal is killed, the terminal process is also killed. Since
the process can do some important things, Eat asks for confirmation
before killing a terminal with running process by default. Eat
provides the user option
eat-query-before-killing-running-terminal to control this.
When set to nil, Eat would never ask. When set to t,
Eat would always ask for confirmation. When set to auto, Eat
would ask only if a shell command is running inside the shell running
in the terminal. This is effective only after shell integration is
enabled in the shell (see Shell Integration) (i.e. after the shell
integration code is executed on shell); before that it is essentially
same as t, and Eat will always query.
Next: Scrollback, Previous: Querying Before Kill, Up: Eat Manual [Contents][Index]
Display is the region you see on the terminal. The program writes to the display and manipulates the text on the display. The display can be of any size. The cursor is always on the display (though it might be invisible sometimes, see Cursor Types).
You can resize the display by resizing the terminal window. The
display size is controlled by the Emacs user option
window-adjust-process-window-size-function. See Process
Buffers in GNU Emacs Lisp Reference Manual for the possible
values of the user option.
Next: Cursor Types, Previous: Display, Up: Eat Manual [Contents][Index]
When you go too downward on the terminal, the terminal starts to “scroll”. This causes the line at the upper side of the terminal to go out of the display and become hidden. But these line are not deleted, they are just put in the scrollback region.
Scrollback region is a region just above the display of the terminal. This contains the lines that went out of display due to scrolling up.
Scrollback region is not unlimited by default, to avoid using too much memory. You can change the limit, or remove it altogether.
This controls the size of scrollback region. It is expressed in
character. If set to size, Eat won’t store more than size
characters in the scrollback region. If set to nil, the
scrollback region is unlimited.
Next: Mouse Tracking, Previous: Scrollback, Up: Eat Manual [Contents][Index]
In terminal, cursor can be of up to three type: “visible”, “invisible” and “very visible”. “Visible” is the default cursor type, which is the cursor you usually see in a shell (unless the shell changes the cursor type). “Invisible” is, as the name suggests, invisible, you can’t see it. “Very visible” cursor is a blinking cursor, programs use this to help you not lose the cursor.
The cursor type can customized with three user options for the three types of cursor. Each of the user options share the same format.
This controls the cursor shape of the “visible” cursor type.
This controls the cursor shape of the “invisible” cursor type.
This controls the cursor shape of the “very visible” cursor type. This cursor blinks, switching between the default cursor shape and a hollow box.
This controls the cursor shape of the “vertical bar” cursor type.
This controls the cursor shape of the “very visible vertical bar” cursor type. This cursor blinks.
This controls the cursor shape of the “horizontal bar” cursor type.
This controls the cursor shape of the “very visible horizontal bar” cursor type. This cursor blinks.
The value type of all these user options is a list. The list is of
form (cursor-on blinking-frequency cursor-off).
blinking-frequency is the frequency of blinking of cursor. It
is a number, controlling how many times the cursor will blink a
second. This can also be nil, this will disable cursor
blinking. cursor-on is the default cursor shape, only this
shape is shown on the display when blinking is disabled. This uses
the same format as Emacs’s cursor-type user option
(see Cursor Display in GNU Emacs Manual). When
blinking-frequency is a number, Eat will consult to the third
element of the list, cursor-off, whose format same as
cursor-on. The blinking cursor switches between cursor-on
and cursor-off cursor shape.
Next: Clipboard, Previous: Cursor Types, Up: Eat Manual [Contents][Index]
Eat tracks mouse by default, when the program supports mouse. But sometimes, you may want to avoid using mouse, or you might not have a mouse at all. So mouse tracking can be toggled.
This user option controls mouse tracking. When set to non-nil,
mouse tracking is enabled. Set to this to nil to disable mouse
tracking. This is enabled by default.
Next: Colors, Previous: Mouse Tracking, Up: Eat Manual [Contents][Index]
Just like any other buffer, you can yank text in terminal with
C-y (bound to eat-yank) or M-y (bound to
eat-yank-pop) in “semi-char mode”.
Programs can also request to the terminal to kill (see Killing in GNU Emacs Manual) something. It is up to Eat whether the request will be fulfilled or not. By default, Eat fulfills the request and kills the text. This can sometimes be annoying, when the program automatically kills text without user interaction. This killing can be configured with the following user option:
This controls killing texts from terminal. When set to
non-nil, killing something from terminal add the text to
Emacs’s kill ring (see Kill Ring in GNU Emacs Manual).
This is enabled by default.
Programs can also request the text in kill ring. Again, this is up to Eat whether the request will be fulfilled or not. You can customize the following user option to configure this:
This controls sending kill ring texts to terminal. When set to
non-nil, programs can receive the kill ring contents. This is
disabled by default for security reasons.
Next: Fonts, Previous: Clipboard, Up: Eat Manual [Contents][Index]
Eat can show more than 16 million colors (16,777,216 colors exactly). Eat has also a palette of 256 colors, which is more than enough for most applications. Programs usually use this color palette. Each of these 256 colors can customized.
There are 256 faces for the 256 colors, one face for each color. They
are named like eat-term-color-n, which corresponds to
color n, and n can be any number between 0 and 255
(inclusive). For example, color 42 is can be changed by customizing
eat-term-color-42.
The foreground attribute contains the color value to use for the corresponding color. Other attributes are currently ignored and reserved for future changes.
Each of the first 16 colors, from eat-term-color-0 to
eat-term-color-15 also have a alias. They are respectively
eat-term-color-black,
eat-term-color-red,
eat-term-color-green,
eat-term-color-yellow,
eat-term-color-blue,
eat-term-color-magenta,
eat-term-color-cyan,
eat-term-color-white,
eat-term-color-bright-black,
eat-term-color-bright-red,
eat-term-color-bright-green,
eat-term-color-bright-yellow,
eat-term-color-bright-blue,
eat-term-color-bright-magenta,
eat-term-color-bright-cyan
and eat-term-color-bright-white.
Eat also supports 24-bit colors, or so called “truecolor”. Programs like Emacs can give a RGB triplet to use as the color of some text. As the programs directly specify the color in this case, you can’t customize these color. But you may configure the program sending the color codes.
Eat doesn’t always advertise color support depending on the display Eat is running. For example, if you are on a Linux console which supports only eight colors, Eat will advertise eight color support to the programs, while on graphical displays with 24-bit color support, Eat will report 24-bit color support. This is because Eat supports more colors, the display doesn’t always support them.
Eat does the trick by setting the TERM environment variable of
the program. The value of TERM depends on the number of the
available colors on the display. This environment variable is
controlled by the following user option:
The value of TERM environment variable as a string. The value
can also be a function taking no arguments, that function should
return a string which used as the value of TERM. The default
value is eat-term-get-suitable-term-name, which is responsible
for the behavior described above.
Next: Sixel, Previous: Colors, Up: Eat Manual [Contents][Index]
Programs may request the terminal to change the text font. It can change text weight, use italic text, or even change the font family altogether.
Programs may request the terminal to show some text bolder than
normal. Bold text uses the face eat-term-bold.
Programs may also request the terminal to show some text fainter than
normal. Faint text uses the face eat-term-faint.
Programs may request the terminal to show italic text too. Italic
text uses the customizable face eat-term-italic.
The number of available fonts is ten. Most of the programs doesn’t change the font. Following many other terminal emulator, Eat actually uses the same font, the default font, regardless of the font requested by the program, by default.
There are ten faces for ten fonts, one face for each. They are named
like eat-term-font-n, which corresponds to color n,
and n can be any number between 0 and 9 (inclusive). For
example, the font 6 is can be changed by customizing
eat-term-font-6. Font 0 is the default font.
Next: Blinking Text, Previous: Fonts, Up: Eat Manual [Contents][Index]
Eat can show Sixel graphics. Sixel is a bitmap graphics format that can be used to display graphics in a terminal, for example, images, or plotting graphs.
You can control the display of Sixel images by customizing the following user options.
This is a non-negative number that specifies the amount to scale the image by.
This is a non-negative number that specifies the aspect ratio, i.e. the ratio of width and height of a Sixel pixel. For example, the value of 2 means the width of a Sixel pixel is the double of its height.
Eat converts Sixel graphics to an image format Emacs can natively
display. This preference of image formats can be configured by
customizing the eat-sixel-render-formats user option.
List of formats to render Sixel, in order of preference. Each element
of the list is one of xpm, svg, half-block,
background, none. xpm and svg means to
use XPM and SVG image format respectively, half-block means to
use UTF-8 half block characters, background means to just use
background color, and none means to not render the image,
instead just clear the area.
Next: Performance Tuning, Previous: Sixel, Up: Eat Manual [Contents][Index]
Programs can request the terminal to blink some text. This helps to get user attention. But however, often this annoying to many people and also has accessiblity problems. So this is disabled by default.
This controls the blinking of text with blink attribute. When set to
non-nil, Eat arranges that text with blink attribute will
blink at a certain interval.
You can toggle blinking temporarily by toggle the buffer-local minor
mode eat-blink-mode. This is only effective in the buffer
where the mode is toggled.
By default, eat-enable-blinking-text is set to nil.
This disables text blinking and causes the text with blink attribute
to be displayed in inverse video (swapped foreground and background).
Programs may also request to blink some text more rapidly that other
blinking text. When blinking is disabled, the face
eat-term-slow-blink is used for slowly blinking text, and
eat-term-fast-blink for rapidly blinking text.
When blinking is enabled, by setting eat-enable-blinking-text
to non-nil value, the following user options can be customized
to change the rate of blinking:
The blinking rate of slowly blinking text. When set to a number N, it causes slowly blinking text to blink N times a second. The value can also be a floating point number. The default value is 2, meaning that the slowing text will blink two times a second.
The blinking rate of rapidly blinking text. When set to a number N, it causes rapidly blinking text to blink N times a second. The value can also be a floating point number as well. The default value is 3, meaning that the slowing text will blink three times a second.
Next: Common Problems, Previous: Blinking Text, Up: Eat Manual [Contents][Index]
Eat tries to be as fast as possible. So Eat employs some techniques to maximize performance.
Some program choke and hang when given too much input at once. So Eat
divides large input to smaller chunks and sends the chunks one at a
time. The maximum size of a input chunk is controlled by
eat-input-chunk-size.
The value is a integer. Eat treat input larger than this many character as large and breaks it into chunks of at most this size before sending the input.
Programs also break large output into smaller chunks before sending it to the terminal, for same reason. Eat doesn’t suffer from the problem, but there isn’t any standard way to inform programs about this, and usually there are other obstructions sending large amount of data at once. These small chunks create another problem for Eat, flickering. When updating the whole display, the output is usually pretty large and the programs break them into smaller chunks. Each of the chunks update the display partially. After receiving the last chunk, the update is complete and the display can be updated. But it is impossible for Eat to guess the last chunk, so Eat has to redisplay or update the display after receiving each chunk. This is the reason why sometimes the terminal shows some old contents and some new. This only lasts for a fraction of a second until the next chunk is received and processed. This is flickering. This also degrades performance, because redisplay is an expensive process and takes some time.
Fixing the flickering completely is not possible. Eat tries to decrease flickering by deferring redisplay. After receiving a chunk, Eat waits for a tiny fraction of a second. If another chunk arrives within the time, the redisplay is postponed. Then Eat waits for the same amount of time and this goes on. When timeout occurs, Eat processing the output and displays the output. This causes a small latency between output arrive and redisplay, but this is usually not long enough for human eyes to catch it. This waiting time can be configured with the following user option:
The value is the time in seconds to wait for the next chunk to arrive. This is the minimum latency between the first chunk after a redisplay and the next redisplay. For example, if you press RET in an empty Bash prompt, the next prompt won’t appear before this much time.
You should set the time to something comfortable for you. You can also set this to zero to disable waiting and showing the output instantly, but this would likely cause a lot of flickering.
However, this waiting raises another problem. What if you execute the POSIX command ‘yes’ in the terminal? It will write infinite “y”s in the terminal without any delay between them anywhere. Eat will wait indefinitely for a delay between two chunks, which will never happen, unless the program is executed remotely and the connection is slow enough. So Eat has a limit for waiting, the display will be always be updated after this time. This limit also customizable:
The value is the time in seconds to wait at most for chunk. In case of large burst of output, redisplay is never deferred more than this many seconds, and cause a latency of up to this many seconds.
You should set the time to something comfortable for you. You can also set this to zero to disable waiting and showing the output instantly, but this would likely cause a lot of flickering.
Due to some limitations, shell prompt annotations (see Shell Integration) can get messed up sometimes. Eat automatically corrects them after each terminal redisplay. However, this can have some performance impact when the terminal scrollback and display is large enough (unless the buffer is narrowed). So Eat defers the correction.
The value is the time in seconds to wait for more output before correcting shell prompt annotations.
You should set the time to something comfortable for you. You can also set this to zero to disable waiting and correct annotations instantly, but this may cause the terminal to slow down in some cases.
The user options described in this chapter have reasonable default values, but the default values may change anytime.
Next: Reporting Bugs, Previous: Performance Tuning, Up: Eat Manual [Contents][Index]
This chapter describe how to recognize and handle situations in which Eat does something unexpected, such as hangs, garbled text, etc.
Next: Garbled Text on Terminal, Up: Common Problems [Contents][Index]
If your program says that it can’t recognize the terminal, probably
the TERM environment variable has a wrong value.
Check the value of TERM, if it’s not set to something like
‘eat-...’, check the user option eat-term-name. If that’s
correct that your shell might be changing the TERM environment
variable. If eat-term-name isn’t correct, customize to a
suitable value and try again, your problem should be fixed.
If TERM has the correct value, then probably the Terminfo
databases of Eat are missing. This can happen if you have installed
Eat without using the package from NonGNU ELPA
(see Packages in GNU Emacs Manual). Check that whether
the values of the environment variable TERMINFO and the user
option eat-term-terminfo-directory match. If they match,
customize eat-term-terminfo-directory to the directory
containing the Terminfo databases, the program should now recognize
Eat. If they don’t match, then your shell is probably responsible for
the problem.
If the program is not recognizing the terminal even when
the correct directory is set as eat-term-terminfo-directory,
probably the precompiled Terminfo databases aren’t working properly on
your system. You can invoke the command
eat-compile-terminfo to recompile it for your system.
If you can’t find the directory containing Terminfo databases, you can
compile it yourself. First, set eat-term-terminfo-directory to
the directory where to put the Terminfo databases. Then invoke the
command eat-compile-terminfo to compile the Terminfo
databases.
Next: Input Invisible, Previous: Terminal Not Recognized, Up: Common Problems [Contents][Index]
If the text on the terminal looks wrong, first check out the value of
TERM. Usually TERM has a wrong value set, making programs
send invalid escape sequences.
First, see Terminal Not Recognized; the problem is most likely because the program doesn’t recognize Eat, and it stays silent instead of reporting that.
If the problem isn’t resolved after following the instructions in the
previous section, probably the precompiled Terminfo databases aren’t
working properly on your system. Running the command
eat-compile-terminfo will recompile it for your system.
If the problem still persists, may be your program is blindly assuming that the terminal is XTerm-compatible. If so, what you are seeing is the current state of “XTerm-compliance”. Though it’s not really a bug, we really want to know what’s problem so that we can fix it and improve XTerm-compliance. See Reporting Bugs for instructions on sending bug reports or feature request.
The other potential reason is that Eat is not working. This is definitely a bug, so please report it.
Next: Emacs or Eat Not Responding, Previous: Garbled Text on Terminal, Up: Common Problems [Contents][Index]
This can happen if the ‘stty’ program is unavailable on the system. Eat uses ‘stty’ to set various terminal settings including input echoing. Please install the ‘stty’ program to fix the problem.
If you are using Eat from Eshell (see Eshell Terminal Emulation), you might
want to set eat-eshell-fallback-if-stty-not-available to handle
such cases. The user option can be set to three possible value,
t to automatically fallback to bare Eshell when ‘stty’ is
not available, nil to do nothing, and ‘ask’ to ask
interactively.
Next: Eat Signaled an Error, Previous: Input Invisible, Up: Common Problems [Contents][Index]
If you run something that outputs huge amount of data, your Emacs may not respond, and even quitting may not work. Quitting doesn’t work while doing something terminal related (output processing, for example), and that’s intentional, because quitting would mess up the terminal.
The best way to fix it is to stop the program, so that Eat is not overloaded. To avoid the problem in future, it is recommended to run those programs in faster terminals like bare Eshell (i.e. without Eat-Eshell), Comint, or external terminal emulators.
Next: Bugs in Manual, Previous: Emacs or Eat Not Responding, Up: Common Problems [Contents][Index]
The worst thing that happen is that Eat might signal an error. It is the worst thing possible, because it messes up the terminal, and also a security hole. Fortunately, this is very rare. If you ever find any such bug, you should report the bug (see Reporting Bugs) as soon as possible with as much information as possible.
Once the error signaled, your best option is to delete the terminal
and start a new one. But if you don’t want to delete the terminal,
you can try invoking the command reset from your shell. If
for some reason you can’t do that, invoke the Emacs command
eat-reset. This will reset most of the terminal state and
give you a clean terminal to work with. However, it mayn’t work if
you’re really unlucky, in that case deleting the terminal and starting
a new one is your only option.
Previous: Eat Signaled an Error, Up: Common Problems [Contents][Index]
Human makes mistake, and we are no exceptions. But we are trying hard to improve Eat and it’s manual.
If you don’t understand something even after a careful rereading, that’s a bug.
If you find anything unclear in this manual, that’s a bug.
This manual’s job is make everything clear, so failing to do that indicates a bug.
If the built-in documentation and this manual don’t agree, one of them must be wrong, and that’s a bug.
If you Eat doesn’t behave as this manual describes, that’s a bug.
If you find any typing mistakes, that’s a bug.
If you find a bug, please report it. See Reporting Bugs for instruction on how to report it.
Next: Tracing the Terminal, Previous: Common Problems, Up: Eat Manual [Contents][Index]
We welcome bug reports and feature request. If you think you have found a bug, please report it. If you’re doubt, please send it anyway. We can’t promise that we’ll fix the bug or implement your feature idea, or always agree that it’s a bug, but we always want to hear from you. Please report bugs at https://codeberg.org/akib/emacs-eat/issues/. You may send the bug report by emailing to the maintainer (M-x describe-package RET eat RET would show the email address), but we prefer the former method, since the report is visible to everyone immediately.
The most important principle in reporting a bug is to report facts. Hypotheses and verbal descriptions are useful when they are more guesses, but in no way substitute for detailed raw data. You are encouraged to send you finding about bug, but please make sure to send the raw data needed to reproduce the bug.
For bug reports, please try to reproduce the bug with ‘emacs -Q’. This will disable loading your Emacs configuration, ruling out the potential bugs in your customizations. Please include enough information for us to reproduce the bug with ‘emacs -Q’, so that we have (or can get) enough information about the bug to fix it. Some bugs are hard to reproduce with ‘emacs -Q’, and some are not easily reproducible at all, in that case please give us the as much information as possible about Emacs configuration. Generally speaking, enough information includes (but not limited to):
emacs -Q, as much
information as possible about Emacs configuration.
When in doubt whether to include something or not, please include it. It is better to include many useless information than to leave out something useful.
It is critical to send enough information to reproduce the bug. What is not critical to “narrow down” the example to the smallest possible – anything that reproduces the bug will suffice. (Of course, if you like doing experiments, the smaller the example, the better.)
Next: GNU General Public License, Previous: Reporting Bugs, Up: Eat Manual [Contents][Index]
When you run into a bug and want to report it, you’ll want to trace the terminal. Tracing means recording all the terminal activity, including creation, output, resizing and deleting.
To enable tracing, enable the global minor mode
eat-trace-mode. This will trace all new terminals,
including the terminal created inside Eshell.
Trace output for each command will be output in a buffer named ‘*eat-trace buffer-name*: command’, where buffer-name is the buffer showing the terminal, and command is the command run in the terminal.
Only the terminals created after the trace mode is enabled are traced. So if you don’t have the mode enabled when you have found a bug, tracing can’t give you any information (as tracing is disabled, nothing has been recorded).
While submitting bug reports, please include the whole output in the trace output buffer. This contains many crucial information required to reproduce your bug.
You can replay the terminal by executing the command
eat-trace-replay is the trace output buffer. You can use
the key n or the key down to show the next frame.
This is not intended for ordinary users, it’s documented here only to
help you debug Eat. You mustn’t rely on the behavior of this
functionality to do anything else.
Next: GNU Free Documentation License, Previous: Tracing the Terminal, Up: Eat Manual [Contents][Index]
Copyright © 2007 Free Software Foundation, Inc. https://fsf.org/ Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The GNU General Public License is a free, copyleft license for software and other kinds of works.
The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program—to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too.
When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.
To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.
For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.
Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it.
For the developers’ and authors’ protection, the GPL clearly explains that there is no warranty for this free software. For both users’ and authors’ sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.
Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users’ freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users.
Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free.
The precise terms and conditions for copying, distribution and modification follow.
“This License” refers to version 3 of the GNU General Public License.
“Copyright” also means copyright-like laws that apply to other kinds of works, such as semiconductor masks.
“The Program” refers to any copyrightable work licensed under this License. Each licensee is addressed as “you”. “Licensees” and “recipients” may be individuals or organizations.
To “modify” a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a “modified version” of the earlier work or a work “based on” the earlier work.
A “covered work” means either the unmodified Program or a work based on the Program.
To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.
To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying.
An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion.
The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-source form of a work.
A “Standard Interface” means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language.
The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it.
The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work’s System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work.
The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source.
The Corresponding Source for a work in source code form is that same work.
All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law.
You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you.
Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary.
No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures.
When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work’s users, your or third parties’ legal rights to forbid circumvention of technological measures.
You may convey verbatim copies of the Program’s source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.
You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.
You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:
A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation’s users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.
You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:
A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.
A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.
“Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.
If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).
The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.
Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.
“Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.
When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission.
Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:
All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying.
If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms.
Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way.
You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10.
You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.
Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License.
An “entity transaction” is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party’s predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts.
You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.
A “contributor” is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor’s “contributor version”.
A contributor’s “essential patent claims” are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, “control” includes the right to grant patent sublicenses in a manner consistent with the requirements of this License.
Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor’s essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.
In the following three paragraphs, a “patent license” is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To “grant” such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.
If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. “Knowingly relying” means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient’s use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid.
If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it.
A patent license is “discriminatory” if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.
Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law.
If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.
Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.
The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation.
If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Program.
Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.
If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.
one line to give the program's name and a brief idea of what it does. Copyright (C) year name of author This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see https://www.gnu.org/licenses/.
Also add information on how to contact you by electronic and paper mail.
If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:
program Copyright (C) year name of author This program comes with ABSOLUTELY NO WARRANTY; for details type ‘show w’. This is free software, and you are welcome to redistribute it under certain conditions; type ‘show c’ for details.
The hypothetical commands ‘show w’ and ‘show c’ should show the appropriate parts of the General Public License. Of course, your program’s commands might be different; for a GUI interface, you would use an “about box”.
You should also get your employer (if you work as a programmer) or school, if any, to sign a “copyright disclaimer” for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see https://www.gnu.org/licenses/.
The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read https://www.gnu.org/licenses/why-not-lgpl.html.
Next: Index, Previous: GNU General Public License, Up: Eat Manual [Contents][Index]
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. https://fsf.org/ Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.
This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.
We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.
This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.
A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.
A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.
The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.
The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.
A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.
Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.
The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.
The “publisher” means any person or entity that distributes copies of the Document to the public.
A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.
The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.
You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.
You may also lend copies, under the same conditions stated above, and you may publicly display copies.
If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.
If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.
You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:
If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.
You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.
You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.
You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.
In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.
A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.
Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/licenses/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright (C) year your name. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:
with the Invariant Sections being list their titles, with
the Front-Cover Texts being list, and with the Back-Cover Texts
being list.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.
Previous: GNU Free Documentation License, Up: Eat Manual [Contents][Index]
| Jump to: | _
A B C D E F G H I K L M N P Q R S T W Y |
|---|
| Jump to: | _
A B C D E F G H I K L M N P Q R S T W Y |
|---|