This manual describes the Emacs EDT package, which provides emulation of DEC’s EDT editor.
This file documents the EDT emulation package for Emacs.
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This manual describes version 4.0 of the EDT Emulation for Emacs. It comes with special functions which replicate nearly all of EDT’s keypad mode behavior. It sets up default keypad and function key bindings which closely match those found in EDT. Support is provided so that users may reconfigure most keypad and function key bindings to their own liking.
Version 4.0 contains several enhancements (see What’s New in Version 4.0).
To start the EDT Emulation, first start Emacs and then enter M-x edt-emulation-on to begin the emulation. After initialization is complete, the following message will appear below the status line informing you that the emulation has been enabled: “Default EDT keymap active”.
You can have the EDT Emulation start up automatically, each time you initiate an Emacs session, by adding the following line to your .emacs file:
(add-hook 'emacs-startup-hook 'edt-emulation-on)
Important: Be sure to read the rest of this manual. It contains very useful information on how the EDT Emulation behaves and how to customize it to your liking.
The EDT emulation consists of the following files:
Version 4.0 contains the following enhancements:
edt-set-scroll-margins in your
.emacs file. For example, the following line
(edt-set-scroll-margins "20%" "25%")
sets the top margin to 20% of the window and the bottom margin
to 25% of the window. To disable this feature, set each margin to 0%.
You can also invoke edt-set-scroll-margins interactively while
EDT Emulation is active to change the settings for that session.
Please note: Another way to set the scroll margins is to use
the Emacs customization feature to set the following two variables
directly: edt-top-scroll-margin and edt-bottom-scroll-margin.
Enter the Emacs customize command. First select the
‘Editing’ group and then select the ‘Emulations’ group.
Finally, select the ‘Edt’ group and follow the directions.
query-replace. The binding of
query-replace has been moved to GOLD-/. If you prefer to
restore query-replace to GOLD-Enter, then use an EDT user
customization file, edt-user.el, to do this
(see Customizing Emulation).
input-decode-map, can still be configured for use with
EDT Emulation. (Note: In a few rare circumstances this does not work
properly. In particular, it does not work if a subset of the leading
ASCII characters in a key sequence are recognized by Emacs as
having an existing binding. For example, if the keypad 7 (KP7)
key generates the sequence ‘ESCOw’ and ‘ESCO’ is already
bound to a function, pressing KP7 when told to do so by
edt-mapper.el will result in edt-mapper.el incorrectly
mapping ‘ESCO’ to KP7 and ‘w’ to KP8. If
something like this happens to you, it is probably a bug in the support
for your keyboard within Emacs or a bug in the Unix
termcap/terminfo support for your terminal or a bug in the
terminal emulation software you are using.)
edt-quit function (bound to GOLD-q by default) has been
modified to warn the user when file-related buffer modifications exist.
It now cautions the user that those modifications will be lost if the
user quits without saving those buffers.
Keyboards used under a Window System are supported via the
edt-mapper function. The first time you invoke the emulation
under a window system, the edt-mapper function is run
automatically and the user is prompted to identify which keys the
emulation is to use for the standard keypad and function keys EDT
expects (e.g., PF1, PF2, KP0, KP1, F1,
F2, etc.). This configuration is saved to disk read each time the
emulation is invoked.
In character oriented connections not running a window manager, built-in support for the following terminals/keyboards is provided:
TERM environment variable is set properly before invoking emacs.
Be sure to read Notes Specific to Certain Platforms to see if those notes apply to you.
Start up Emacs and enter M-x edt-emulation-on to begin the emulation. After initialization is complete, the following message will appear below the status line informing you that the emulation has been enabled: “Default EDT keymap active”.
You can have the EDT Emulation start up automatically, each time you initiate an Emacs session, by adding the following line to your .emacs file:
(add-hook 'emacs-startup-hook 'edt-emulation-on)
A reference sheet is included (later on) listing the default EDT Emulation key bindings. This sheet is also accessible on line from within Emacs by pressing PF2, GOLD-H, or ‘HELP’ (when in the EDT Default Mode).
It is easy to customize key bindings in the EDT Emulation (see Customizing Emulation). Customizations are placed in a file called edt-user.el. The Emacs etc/ directory contains an example. If edt-user.el is found in your Emacs load path during EDT Emulation initialization, then the following message will appear below the status line indicating that the emulation has been enabled, enhanced by your own customizations: “User EDT custom keymap active”.
Once enabled, it is easy to switch back and forth between your
customized EDT Emulation key bindings and the default EDT Emulation key
bindings. (Look at the binding to GOLD-Z in the sample
edt-user.el file.) It is also easy to turn off the emulation
(via the command edt-emulation-off). Doing so completely
restores the original key bindings in effect just prior to invoking the
emulation.
Emacs binds keys to ASCII control characters and so does the real EDT. Where EDT key bindings and Emacs key bindings conflict, the default Emacs key bindings are retained by the EDT emulation by default. If you are a die-hard EDT user you may not like this. The Enabling EDT Control Key Sequence Bindings section explains how to change this so that the EDT bindings to ASCII control characters override the default Emacs bindings.
Some earlier Sun keyboards do not have arrow keys separate from the keypad keys. It is difficult to emulate the full EDT keypad and still retain use of the arrow keys on such keyboards.
The Sun Type 5 and other more recent Sun keyboards, however, do have separate arrow keys. This makes them candidates for setting up a reasonable EDT keypad emulation.
Depending upon the configuration of the version of X installed on your system, you may find the default X keynames for the keypad keys don’t permit Emacs to interpret some or all the keypad keys as something other than arrow keys, numeric keys, Home, PageUp, etc. Both Sun and HP have been particularly guilty of making bizarre keysym assignments to the keypad keys.
In most cases, the X Windows command, xmodmap, can be used to
correct the problem. Here’s a sample .xmodmaprc file which
corrects this problem on one Sun workstation configuration using an
older SunOS release configured with a Sun Type 5 keyboard:
! File: .xmodmaprc ! ! Set up Sun Type 5 keypad for use with the Emacs EDT Emulation ! keycode 53 = KP_Divide keycode 54 = KP_Multiply keycode 57 = KP_Decimal keycode 75 = KP_7 keycode 76 = KP_8 keycode 77 = KP_9 keycode 78 = KP_Subtract keycode 97 = KP_Enter keycode 98 = KP_4 keycode 99 = KP_5 keycode 100 = KP_6 keycode 101 = KP_0 keycode 105 = F24 keycode 119 = KP_1 keycode 120 = KP_2 keycode 121 = KP_3 keycode 132 = KP_Add
If edt-mapper.el does not recognize your keypad keys as unique keys, use the command ‘xmodmap -pke’ to get a listing of the actual key codes and the keysyms mapped to them and then generate you own custom .xmodmaprc similar to the one above.
Next, feed .xmodmaprc to the xmodmap command and all the
Sun Type 5 keypad keys will now be configurable for the emulation of an
LK-201 keypad (less the , key). In this example, the line
keycode 105 = F24
changes the X Windows name of the keypad NumLock key to be known internally as the F24 key. Doing so permits it to be configured to behave as the PF1 (GOLD) key.
The side effect of this change is that you will no longer have a NumLock key. If you are using other software under X which requires a NumLock key, then examine your keyboard and look for one you don’t use and redefine it to be the NumLock key. Basically, you need to clear the NumLock key from being assigned as a modifier, assign it to the key of your choice, and then add it back as a modifier. (General Notes on Using NumLock for the PF1 Key on Unix Systems for further help on how to do this.)
By default, F1 is configured to emulate the PF1 (GOLD) key. But NumLock can be used instead if you load a freeware TSR distributed with MS-Kermit, call ‘gold.com’. This was once distributed in a file called gold22.zip and came with the source code as well as a loadable binary image. (See edt-pc.el in the Emacs lisp/emulation directory for more information.)
The default X server configuration varies from distribution to
distribution and release to release of GNU/Linux. If your system fails
to recognize the keypad keys as distinct keys, change the NumLock state,
turning it on or off, as the case may be, then try again. If this
doesn’t solve your problem, you may have to modify the X keysym mappings
with xmodmap.
On one distribution on an Intel PC, the following .xmodmaprc set things up nicely.
! File: .xmodmaprc ! ! Set up PC keypad under GNU/Linux for the Emacs EDT Emulation ! clear mod2 keycode 77 = F12 keycode 96 = Num_Lock Pointer_EnableKeys add mod2 = Num_Lock
In this example, after feeding the file to the xmodmap command,
the PC NumLock keypad key will be configurable for the emulation
of the PF1 key. The PC keypad can now emulate an LK-201 keypad
(less the comma key), the standard keyboard supplied with DEC terminals
VT-200 and above. This .xmodmaprc file switches the role of the
F12 and NumLock keys. It has been tested on Red Hat
GNU/Linux 5.2. Other versions of GNU/Linux may require different
keycodes. (General Notes on Using NumLock for the PF1 Key on Unix Systems for further help on how to do this.)
Please note: Remember, it may be necessary to have NumLock in one position (ON) or the other (OFF) for the PC keypad to emulate the LK-201 keypad properly.
Making the physical NumLock key available for use in the EDT Emulation requires some modification to the default X Window settings. Since the keycode assignments vary from system to system, some investigation is needed to see how to do this on a particular system.
You will need to look at the output generated by xmodmap invoked
with the "-pm" switch. For example, on Red Hat GNU/Linux 5.2 on a PC, we
get the following output when running ‘xmodmap -pm’:
xmodmap: up to 2 keys per modifier, (keycodes in parentheses): shift Shift_L (0x32), Shift_R (0x3e) lock Caps_Lock (0x42) control Control_L (0x25), Control_R (0x6d) mod1 Alt_L (0x40), Alt_R (0x71) mod2 Num_Lock (0x4d) mod3 mod4 mod5 Scroll_Lock (0x4e)
Note that Num_Lock is assigned to the modifier ‘mod2’. This is what hides Num_Lock from being seen by Emacs.
Now, ‘xmodmap -pke’ yields:
. . . keycode 77 = Num_Lock Pointer_EnableKeys . . . keycode 96 = F12 . . .
So, in Red Hat GNU/Linux 5.2 on a PC, Num_Lock generates keycode 77. The following steps are taken:
The .xmodmaprc file looks like this:
! File: .xmodmaprc ! ! Set up PC keypad under GNU/Linux for the Emacs EDT Emulation ! clear mod2 keycode 77 = F12 keycode 96 = Num_Lock Pointer_EnableKeys add mod2 = Num_Lock
So, after executing ‘xmodmap .xmodmaprc’, a press of the physical F12 key looks like a Num_Lock keypress to X. Also, a press of the physical NumLock key looks like a press of the F12 key to X.
Now, edt-mapper.el will see ‘f12’ when the physical NumLock key is pressed, allowing the NumLock key to be used as the EDT PF1 (GOLD) key.
In general, you will find that this emulation of EDT replicates most, but not all, of EDT’s most used Keypad Mode editing functions and behavior. It is not perfect, but most EDT users who have tried the emulation agree that it is quite good enough to make it easy for die-hard EDT users to move over to using Emacs.
Here’s a list of the most important differences between EDT and this GNU Emacs EDT Emulation. The list is short but you must be aware of these differences if you are to use the EDT Emulation effectively.
EDT allows users to enter a repeat count before entering a command that accepts repeat counts. For example, when using the real EDT, pressing these three keys in sequence, GOLD 5 KP1, will move the cursor in the current direction 5 words. This does not work in Emacs!
Emacs provides two ways to enter repeat counts and neither involves
using the GOLD key. First, repeat counts can be entered in Emacs
by using the ESC key. For example, pressing these keys in
sequence, ESC 1 0 KP1, will move the cursor in the current
direction 10 words. Second, Emacs provides another command called
universal-argument that can be used to do the same thing.
Normally, in Emacs has this bound to C-u.
To enter Emacs commands not bound to keys, you can press GOLD KP7 or the DO key. Emacs will display its own command prompt "M-x". This stands for the keypress Meta-x, where Meta is a special shift key. The Alt key is often mapped to behave as a Meta key. So, you can also invoke this prompt by pressing Meta-x. Typing the sequence ESC x will also invoke the prompt.
edt-define-key) and is
bound to C-k in the default EDT mode when EDT control sequence
bindings are enabled, or when the sample edt-user.el
customization file is used. The TPU/EVE learn command is supported but
not bound to a key in the default EDT mode but is bound in the sample
edt-user.el file.
Unlike the TPU/EVE learn command, which uses one key to begin the learn
sequence, C-l, and another command to remember the sequence,
C-r, this version of the learn command (edt-learn) serves
as a toggle to both begin and to remember the learn sequence.
Many users who change the meaning of a key with the define key and the learn commands, would like to be able to restore the original key binding without having to quit and restart emacs. So a restore key command is provided to do just that. When invoked, it prompts you to press the key to which you wish the last replaced key definition restored. It is bound to GOLD C-k in the default EDT mode when EDT control sequence bindings are enabled or the sample edt-user.el customization file is used.
edt-emulation-off, at the ‘M-x’ prompt and the original
Emacs bindings will be restored. To resume the EDT emulation, just
enter edt-emulation-on.
query-replace function, which we find to be easier to use.
page-delimiter to determine
what marks a page break. This is normally ‘^\f’, which causes the
edt-page command to ignore form feeds not located at the
beginning of a line. To emulate the EDT ‘PAGE’ command exactly,
page-delimiter is set to ‘\f’ when EDT emulation is turned on, and
restored to ‘^\f’ when EDT emulation is turned off. But, since
some users prefer the Emacs definition of a page break, or may wish to
preserve a customized definition of page break, one can override the EDT
definition by placing
(setq edt-keep-current-page-delimiter t)
in your .emacs file. Or, you can used the Emacs customize command to change its setting.
edt-scroll-window function which you may prefer over the
‘SECT’ emulation.)
edt-lowercase and edt-uppercase.
They work on individual words or selected text, if
‘SELECT’ is active.
edt-duplicate-word, is provided. If you
experiment with it, you might find it to be surprisingly useful and may
wonder how you ever got along without it! It is assigned to C-j
in the sample edt-user.el customization file.
Nevertheless, there are still many GOLD key sequences which are not bound to any functions. These are prime candidates to use for your own customizations.
Also, there are several commands in edt.el not bound to any key. So, you will find it worthwhile to look through edt.el for functions you may wish to add to your personal customized bindings.
In addition, our VT220 terminals generate an interrupt when the F6 key is pressed (‘^C’ or ‘^Y’, can’t remember which) and not the character sequence documented in the manual. So, binding Emacs commands to F6 will not work if your terminal behaves the same way.
We also provide a TPU/EVE like version of the single ‘SELECT/RESET’
function, called edt-toggle-select, which makes the EDT
‘SELECT’ function into a toggle on/off switch. That is, if
selection is on, pressing ‘SELECT’ again turns selection off
(cancels selection). This function is used in the sample
edt-user.el customization file.
Most EDT users, at one time or another, make some custom key bindings, or use someone else’s custom key bindings, which they come to depend upon just as if they were built-in bindings. This EDT Emulation for GNU Emacs is designed to make it easy to customize bindings.
If you wish to customize the EDT Emulation to use some of your own key bindings, you need to make a private version of edt-user.el in your own private lisp directory. The Emacs etc/ directory contains an example for you to use as a template and for ideas.
First, you need to have your own private lisp directory, say ~/lisp, and you should add it to the Emacs load path.
Please note: A few sites have different load-path requirements, so the above directions may need some modification if your site has such special needs.
A sample edt-user.el file is provided in the Emacs etc/ directory. You should use it as a guide to learn how you can customize EDT emulation bindings to your own liking. Names used to identify the set of LK-201 keypad and function keys are:
Keypad Keys:
PF1 PF2 PF3 PF4
KP7 KP8 KP9 KP-
KP4 KP5 KP6 KP,
KP1 KP2 KP3
KP0 KPP KPE
Arrow Keys:
LEFT RIGHT DOWN UP
Function Keys:
F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 F13 F14
HELP DO F17 F18 F19 F20
FIND INSERT REMOVE
SELECT PREVIOUS NEXT
Note: Many VT-200 terminals, and above, steal function keys F1 through F5 for terminal setup control and don’t send anything to the host if pressed. So customizing bindings to these keys may not work for you.
There are three basic functions that do the EDT emulation custom
bindings: edt-bind-key, edt-bind-gold-key, and
edt-bind-function-key.
The first two are for binding functions to keys which are standard across most keyboards. This makes them keyboard independent, making it possible to define these key bindings for all terminals in the file edt.el.
The first, edt-bind-key, is used typically to bind emacs commands
to control keys, although some people use it to bind commands to other
keys, as well. (For example, some people use it to bind the VT200
seldom used back-tick key (‘`’) to the function ‘ESC-prefix’
so it will behave like an ESC key.) The second function,
edt-bind-gold-key, is used to bind emacs commands to gold key
sequences involving alphanumeric keys, special character keys, and
control keys.
The third function, edt-bind-function-key, is terminal dependent
and is defined in a terminal specific file (see edt-vt100.el for
example). It is used to bind emacs commands to LK-201 function keys, to
keypad keys, and to gold sequences of those keys.
The variable edt-word-entities is used to emulate EDT’s ‘SET
ENTITY WORD’ command. It contains a list of characters to be treated as
words in themselves. If the user does not define
edt-word-entities in his/her .emacs file, then it is set
up with the EDT default containing only TAB.
The characters are stored in the list by their numerical values, not as strings. Emacs supports several ways to specify the numerical value of a character. One method is to use the question mark: ‘?A’ means the numerical value for ‘A’, ‘?/’ means the numerical value for ‘/’, and so on. Several unprintable characters have special representations:
?\b specifies BS, C-h ?\t specifies TAB, C-i ?\n specifies LFD, C-j ?\v specifies VTAB, C-k ?\f specifies FF, C-l ?\r specifies CR, C-m ?\e specifies ESC, C-[ ?\\ specifies \
Here are some examples:
(setq edt-word-entities '(?\t ?- ?/)) ; specifies TAB, - , and / (setq edt-word-entities '(?\t) ; specifies TAB, the default
You can also specify characters by their decimal ASCII values:
(setq edt-word-entities '(9 45 47)) ; specifies TAB, - , and /
Where EDT key bindings and Emacs key bindings conflict, the default
Emacs key bindings are retained by default. Some die-hard EDT users
may not like this. So, if the variable
edt-use-EDT-control-key-bindings is set to true in a user’s
.emacs file, then the default EDT Emulation mode will enable most
of the original EDT control key sequence bindings. If you wish to do
this, add the following line to your .emacs file:
(setq edt-use-EDT-control-key-bindings t)
Scroll margins at the top and bottom of the window are now supported.
(The design was copied from tpu-extras.el.) By default, this
feature is enabled with the top margin set to 10% of the window and the
bottom margin set to 15% of the window. To change these settings, you
can invoke the function edt-set-scroll-margins in your
.emacs file. For example, the following line
(edt-set-scroll-margins "20%" "25%")
sets the top margin to 20% of the window and the bottom margin
to 25% of the window. To disable this feature, set each margin to 0%.
You can also invoke edt-set-scroll-margins interactively while
EDT Emulation is active to change the settings for that session.
Please note: Another way to set the scroll margins is to use
the Emacs customization feature to set the following two variables
directly: edt-top-scroll-margin and edt-bottom-scroll-margin.
Enter the Emacs customize command. First select the
‘Editing’ group and then select the ‘Emulations’ group.
Finally, select the ‘Edt’ group and follow the directions.
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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.