This manual describes PCL-CVS, the GNU Emacs front-end to CVS. It is nowhere near complete, so you are advised to use M-x customize-group RET pcl-cvs RET and to look at the documentation strings of the various commands and major modes for further information.
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PCL-CVS is a front-end to CVS versions 1.9 and later.
It concisely shows the present status of a checked out module in an
Emacs buffer and provides single-key access to the most frequently used CVS
commands. Note that the vc-dir command (see VC Directory
Mode in The GNU Emacs Manual) provides similar
functionality, but for several version control systems, including CVS.
PCL-CVS was originally written many years ago by Per Cederqvist who proudly maintained it until January 1996, at which point he released the beta version 2.0b2 and passed on the maintainership to Greg A Woods. Development stayed mostly dormant for a few years during which version 2.0 never seemed to be able to leave the “beta” stage while a separate XEmacs version was slowly splitting away. In late 1998, Stefan Monnier picked up development again, adding some major new functionality and taking over the maintenance.
Contributions to the package are welcome. I have limited time to work on this project, but I will gladly add any code that you contribute to me to this package (see Bugs (known and unknown)).
The following persons have made contributions to PCL-CVS.
cvs-status-mode.
Apart from these, a lot of people have sent us suggestions, ideas, requests, bug reports and encouragement. Thanks a lot! Without you there would be no new releases of PCL-CVS.
This document assumes that you know what CVS is, and that you at least know the fundamental concepts of CVS. If that is not the case, you should read the CVS documentation. Type info -f cvs or man cvs.
PCL-CVS is only useful once you have checked out a module. So before you invoke it, you must have a copy of a module somewhere in the file system.
You can invoke PCL-CVS by typing M-x cvs-examine RET. You can also invoke it via the menu bar, under ‘Tools’. Or, if you prefer, you can also invoke PCL-CVS by simply visiting the CVS administrative subdirectory of your module, with a prefix argument. For example, to invoke PCL-CVS in a separate frame, type C-u C-x 5 f ~/my/project/CVS RET.
The function cvs-examine will ask for a directory. The command
‘cvs -n update’ will be run in that directory. (It should contain
files that have been checked out from a CVS archive.) The output from
cvs will be parsed and presented in a table in a buffer called
*cvs*. It might look something like this:
Repository : /usr/CVSroot
Module : test
Working dir: /users/ceder/FOO/test
In directory .:
Need-Update bar
Need-Update file.txt
Modified namechange
Need-Update newer
In directory sub:
Modified ChangeLog
--------------------- End ---------------------
-- last cmd: cvs -f -z6 -n update -d -P --
In this example, your repository is in /usr/CVSroot and CVS has been run in the directory /users/ceder/FOO/test. The three files (bar, file.txt and newer) that are marked with ‘Need-Update’ have been changed by someone else in the CVS repository. Two files (namechange and sub/ChangeLog) have been modified locally, and need to be checked in.
You can move the cursor up and down in the buffer with C-n and C-p or n and p. If you press c on one of the ‘Modified’ files, that file will be checked in to the CVS repository. See Committing changes. You can also press O to update any of the files that are marked ‘Need-Update’. You can also run M-x cvs-update RET (bound to M-u in the *cvs* buffer) to update all the files.
You can then press = to easily get a ‘diff’ between your modified file and the base version that you started from, or you can press l to get the output from ‘cvs log’. Many more such commands are available simply by pressing a key (see Getting info about files).
The display contains several columns, some of which are optional. These columns are, from left to right:
The ‘file status’ field can have the following values:
The file is modified in your working directory, and there was no modification to the same file in the repository. This status can have the following substatus:
The file was modified in your working directory, and there were modifications in the repository as well, but they were merged successfully, without conflict, in your working directory.
A conflict was detected while trying to merge your changes to file
with changes from the repository. file (the copy in your
working directory) is now the output of the rcsmerge command on
the two versions; an unmodified copy of your file is also in your
working directory, with the name .#file.version,
where version is the RCS revision that your modified file started
from. See Viewing differences, for more details.
A conflict can also come from a disagreement on the existence of the file rather than on its content. This case is indicated by the following possible substatus:
The file is locally removed but a new revision has been committed to the repository by someone else.
The file is locally added and has also been added to the repository by someone else.
The file is locally modified but someone else has removed it from the repository.
The file has been added by you, but it still needs to be checked in to the repository.
The file has been removed by you, but it still needs to be checked in to the repository. You can resurrect it by typing a (see Adding and removing files).
A file that was detected in your directory, but that neither appears in the repository, nor is present on the list of files that CVS should ignore.
The file is up to date with respect to the version in the repository. This status can have a substatus of:
You have just added the file to the repository.
The file was brought up to date with respect to the repository. This is done for any file that exists in the repository but not in your source, and for files that you haven’t changed but are not the most recent versions available in the repository.
The file was brought up to date with respect to the remote repository by way of fetching and applying a patch to the file in your source. This is equivalent to ‘updated’ except that CVS decided to use a hopefully more efficient method.
You just committed the file.
Either a newer version than the one in your source is available in the repository and you have not modified your checked out version, or the file exists in the repository but not in your source. Use ‘cvs-mode-update’ bound to O to update the file.
You have modified the checked out version of the file, and a newer version is available in the repository. A merge will take place when you run a ‘cvs-update’.
The file has been unexpectedly removed from your working directory although it has not been ‘cvs remove’d.
Many of the commands work on the current set of selected files which can be either the set of marked files (if any file is marked and marks are not ignored) or whichever file or directory the cursor is on.
If a directory is selected but the command cannot be applied to a directory, then it will be applied to the set of files under this directory which are in the *cvs* buffer.
Furthermore, each command only operates on a subset of the selected
files, depending on whether or not the command is applicable to
each file (based on the file’s status). For example,
cvs-mode-commit is not applicable to a file whose status is
‘Need-Update’. If it should happen that PCL-CVS guesses the
applicability wrong, you can override it with the special prefix
cvs-mode-force-command normally bound to M-f (and file a
bug report). The applicability rule can be slightly changed with
cvs-allow-dir-commit and cvs-force-dir-tag.
By default, marks are always in effect (you may change this, however, by
setting the variable cvs-default-ignore-marks) except for the
commands that ‘tag’ or ‘diff’ a file (which can be changed
with the variable cvs-invert-ignore-marks).
In addition, you may use the special prefix cvs-mode-toggle-marks
normally bound to T to toggle the use of marks for the following
command.
This scheme might seem a little complicated, but once one gets used to it, it is quite powerful.
For commands to mark and unmark files, see Marking files.
The nodes in this menu contains explanations about all the commands that you can use in PCL-CVS. They are grouped together by type.
Most commands in PCL-CVS require that you have a *cvs* buffer. The commands that you use to get one are listed below. For each, a ‘cvs’ process will be run, the output will be parsed by PCL-CVS, and the result will be printed in the *cvs* buffer (see Buffer contents, for a description of the buffer’s contents).
Run a ‘cvs update’ command. You will be asked for the directory in which the ‘cvs update’ will be run.
Run a ‘cvs -n update’ command. This is identical to the previous command, except that it will only check what needs to be done but will not change anything. You will be asked for the directory in which the ‘cvs -n update’ will be run.
Run a ‘cvs status’ command. You will be asked for the directory in which the ‘cvs status’ will be run.
Run a ‘cvs checkout’ command. You will be asked for the directory in which the ‘cvs update’ will be run and the module to be checked out.
Populate the *cvs* buffer by just looking at the CVS/Entries
files. This is very much like cvs-examine except that it does
not access the CVS repository, which is a major advantage when the
repository is far away. But of course, it will not be able to detect
when a file needs to be updated or merged.
The first four of
those commands are also reachable from the menu bar
under ‘Tools->PCL-CVS’. Finally, an alternative way is to visit
the CVS administrative subdirectory in your work area with a simple
prefix argument. For example C-u C-x C-f ~/my/work/CVS RET. This
by default runs cvs-quickdir but the specific behavior can be
changed with cvs-dired-action and cvs-dired-use-hook.
By default, the commands above will descend recursively into subdirectories. You can avoid that behavior by including ‘-l’ in the flags for the command. These flags can be set by giving a prefix argument to the command (e.g., by typing C-u M-x cvs-update RET -l RET).
This section describes the convention used by nearly all PCL-CVS commands for setting optional flags sent to CVS. A single C-u prefix argument is used to cause the command to prompt for flags to be used for the current invocation of the command only. Two C-u prefix arguments are used to prompt for flags which will be set permanently, for the current invocation and all that follow, until the flags are changed, or unless temporary flags are set which override them.
Perhaps an example or two is in order. Say you are about to add a binary file to the repository, and want to specify the flags ‘-kb’ to ‘cvs add’. You can type C-u a -kb RET, and the file will be added. Subsequent ‘cvs add’ commands will use the previously prevailing flags.
As a second example, say you are about to perform a diff and want to see
the result in unified diff format, i.e., you’d like to pass the flag
‘-u’ to both ‘cvs diff’ and ‘diff’. You’d also like all
subsequent diffs to use this flag. You can type C-u C-u = -u RET
and the diff will be performed, and the default flags will be set to
("-u"). You can of course override this flag for a single diff
by using a single C-u prefix argument.
In addition to this, some commands can take special prefix arguments. These work as follows: When called with a C-u prefix, the user is prompted for a new value of the special prefix and the special prefix is activated for the next command. When called without the C-u prefix, the special prefix is re-activated (with the same value as last time) for the next command. Calling the prefix command again when it’s already activated deactivates it. Calling it with the C-u C-u prefix activates it for all subsequent commands until you deactivate it explicitly. The special prefixes are:
Toggles whether or not marks will be active in the next command.
Provide the next command with a branch (can be any version specifier) to work on.
Secondary branch argument. Only meaningful if b is also used.
It can be used to provide a second branch argument to
cvs-mode-diff or to cvs-mode-update.
Forces the next command to apply to every selected file rather than only to the ones PCL-CVS thinks are relevant.
The following commands can be used from within the *cvs* buffer to update the display:
Runs the command ‘cvs-update’.
Runs the command ‘cvs-examine’.
Runs the command ‘cvs-status’.
In addition to the above commands which operate on the whole module, you can run the equivalent CVS command on just a subset of the files/directories with these keys:
Runs cvs-mode-update on the selected files. When run on the
top-level directory, this is equivalent to M-u.
Runs cvs-mode-examine on the selected files. When run on the
top-level directory, this is equivalent to M-e.
Runs cvs-mode-status on the selected files. When run on the
top-level directory, this is equivalent to M-s, except that
CVS output will be shown in a *cvs-info* buffer that will be
put in ‘cvs-status-mode’.
You can use most normal Emacs commands to move forward and backward in the buffer. Some keys are rebound to functions that take advantage of the fact that the buffer is a PCL-CVS buffer:
These keys move the cursor one file forward, towards the end of the
buffer (cvs-mode-next-line).
This key moves one file backward, towards the beginning of the buffer
(cvs-mode-previous-line).
PCL-CVS works on a set of selected files (see Selected files). You can mark and unmark files with these commands:
This marks the file that the cursor is positioned on. If the cursor is
positioned on a directory all files in that directory are marked
(cvs-mode-mark).
Unmark the file that the cursor is positioned on. If the cursor is on a
directory, all files in that directory are unmarked
(cvs-mode-unmark).
Mark all files in the buffer (cvs-mode-mark-all-files).
Unmark all files (cvs-mode-unmark-all-files).
Unmark the file on the previous line, and move point to that line
(cvs-mode-unmark-up).
Mark all files matching a regular expression
(cvs-mode-mark-matching-files).
Mark all files in a particular state, such as “Modified” or
“Removed” (cvs-mode-mark-on-state).
Toggle use of marks for the next command (cvs-mode-toggle-marks).
Committing changes basically works as follows:
There’s no hidden state, so you can abort the process or pick it up again at any time.
The set of files actually committed is really decided only during the
very last step, which is a mixed blessing. It allows you to go back and
change your mind about which files to commit, but it also means that you
might inadvertently change the set of selected files. To reduce the
risk of error, C-c C-c will ask for confirmation if the set of
selected files has changed between the first step and the last. You can
change this last detail with log-edit-confirm.
As for the difference between c (i.e., cvs-mode-commit) and
C (i.e., cvs-mode-commit-setup) is that the first gets you
straight to *cvs-commit* without erasing it or changing anything
to its content, while the second first erases *cvs-commit*
and tries to initialize it with a sane default (it does that by either
using a template provided by the CVS administrator or by extracting a
relevant log message from a ChangeLog file).
If you are editing the files in your Emacs, an automatic ‘revert-buffer’ will be performed. (If the file contains ‘$Id$’ keywords, ‘cvs commit’ will write a new file with the new values substituted. The auto-revert makes sure that you get them into your buffer.) The revert will not occur if you have modified your buffer, or if ‘cvs-auto-revert’ is set to ‘nil’.
There are currently three commands that can be used to find a file (that is, load it into a buffer and start editing it there). These commands work on the line that the cursor is situated at. They always ignore any marked files.
Find the file that the cursor points to (cvs-mode-find-file). If
the cursor points to a directory, run dired on that directory;
see Emacs Manual.
Like f, but use another window
(cvs-mode-find-file-other-window).
Invoke ‘add-change-log-entry-other-window’ to edit a
ChangeLog file. The ChangeLog file will be found in the
directory of the file the cursor points to, or in a parent of that
directory (cvs-mode-add-change-log-entry-other-window).
Call the command cvs-mode-log which runs ‘cvs log’ on all
selected files, and show the result in a temporary buffer
*cvs-info* (see Browsing a Log of Changes).
Call the command cvs-mode-status which runs ‘cvs status’ on
all selected files, and show the result in a temporary buffer
*cvs-info*.
The following commands are available to make it easy to add files to and remove them from the CVS repository.
Add all selected files. This command can be used on ‘Unknown’ files (see Buffer contents). The status of the file will change to ‘Added’, and you will have to use c (‘cvs-mode-commit’ see Committing changes), to really add the file to the repository.
This command can also be used on ‘Removed’ files (before you commit them) to resurrect them.
The command that is run is cvs-mode-add.
This command removes the selected files (after prompting for confirmation). The files are deleted from your directory and (unless the status was ‘Unknown’; see Buffer contents) they will also be ‘cvs remove’d. If the files’ status was ‘Unknown’ they will disappear from the buffer. Otherwise their status will change to ‘Removed’, and you must use c (‘cvs-mode-commit’, see Committing changes) to commit the removal.
The command that is run is cvs-mode-remove-file.
If you have modified a file, and for some reason decide that you don’t
want to keep the changes, you can undo them with this command. It works
by removing your working copy of the file and then getting the latest
version from the repository (cvs-mode-undo-local-changes).
This command allows you to remove all entries that you have processed. More specifically, the lines for ‘Up-to-date’ files (see Buffer contents) are removed from the buffer. If a directory becomes empty the heading for that directory is also removed. This makes it easier to get an overview of what needs to be done.
x invokes cvs-mode-remove-handled. If
‘cvs-auto-remove-handled’ is set to non-nil, this will
automatically be performed after every commit.
This command can be used for lines that ‘cvs-mode-remove-handled’ would
not delete, but that you want to delete (cvs-mode-acknowledge).
Arrange so that CVS will ignore the selected files. The file names are added to the .cvsignore file in the corresponding directory. If the .cvsignore file doesn’t exist, it will be created.
The .cvsignore file should normally be added to the repository, but you could ignore it as well, if you like it better that way.
This runs cvs-mode-ignore.
Display a ‘cvs diff’ between the selected files and the version
that they are based on (cvs-mode-diff).
If CVS finds a conflict while merging two versions of a file (during a ‘cvs update’, see Updating the *cvs* buffer) it will save the original file in a file called .#file.version where file is the name of the file, and version is the revision number that file was based on.
With the d b command you can run a ‘diff’ on the files .#file.version and file.
Display a ‘cvs diff’ between the selected files and the head
revision (the most recent version on the current
branch) in the repository (cvs-mode-diff-head).
Display a ‘cvs diff’ between the base revision of the selected
files and the head revision in the repository. This displays the
changes anyone has committed to the repository since you last executed
a checkout, update or commit operation
(cvs-mode-diff-repository).
Display a ‘cvs diff’ between the selected files and the head
revision of the vendor branch in the repository
(cvs-mode-diff-vendor).
Display a ‘cvs diff’ between the selected files and yesterday’s
head revision in the repository
(cvs-mode-diff-yesterday).
By default, ‘diff’ commands ignore the marks. This can be changed
with cvs-invert-ignore-marks.
This uses ediff (or emerge, depending on
‘cvs-idiff-imerge-handlers’) to allow you to view diffs.
If a prefix argument is given, PCL-CVS will prompt for a revision against
which the diff should be made, else the default will be to use the BASE
revision.
This command use ediff (or emerge, see above) to allow you
to do an interactive 3-way merge.
Please note: when the file status is ‘Conflict’, CVS has already performed a merge. The resulting file is not used in any way if you use this command. If you use the q command inside ‘ediff’ (to successfully terminate a merge) the file that CVS created will be overwritten.
Update all selected files with status ‘Need-update’ by running
‘cvs update’ on them (cvs-mode-update).
Tag all selected files by running ‘cvs tag’ on
them (cvs-mode-tag). It’s usually preferable to tag a directory
at a time. Rather than selecting all files (which too often doesn’t
select all files but only the few that are displayed), clear the
selection with M-DEL (cvs-mode-unmark-all-files), position
the cursor on the directory you want to tag and hit t.
By default, ‘tag’ commands ignore the marks. This can be changed
with cvs-invert-ignore-marks. Also, by default ‘tag’ can
only be applied to directories, see cvs-force-dir-tag if you want
to change this behavior.
Byte compile all selected files that end in .el.
This command deletes the lock files that the *cvs* buffer informs you about. You should normally never have to use this command, since CVS tries very carefully to always remove the lock files itself.
You can only use this command when a message in the *cvs* buffer tells
you so. You should wait a while before using this command in case
someone else is running a cvs command.
Also note that this only works if the repository is local.
Show a summary of common command key bindings in the echo
area (cvs-help).
Bury the PCL-CVS buffer (cvs-bury-buffer).
Quit PCL-CVS, killing the *cvs* buffer.
Buffers for entering/editing log messages for changes which are about to be committed are put into Log Edit mode.
Sometimes the log buffer contains default text when you enter it, typically the last log message entered. If it does, mark and point are set around the entire contents of the buffer so that it is easy to kill the contents of the buffer with C-w.
If you work by writing entries in the ChangeLog (see Change Log in The GNU Emacs Manual) and then commit the change under revision control, you can generate the Log Edit text from the ChangeLog using C-c C-a (log-edit-insert-changelog). This looks for entries for the file(s) concerned in the top entry in the ChangeLog and uses those paragraphs as the log text. This text is only inserted if the top entry was made under your user name on the current date. See Change Logs and VC in The GNU Emacs Manual, for the opposite way of working—generating ChangeLog entries from the revision control log.
In the Log Edit buffer, C-c C-f (M-x log-edit-show-files) shows the list of files to be committed in case you need to check that.
When you have finished editing the log message, type C-c C-c to exit the buffer and commit the change.
Log View mode provides a few useful commands for navigating revision
control log output. It is used for the output buffers of both
cvs-mode-log and vc-print-log.
In this mode, n goes to the next message and p goes to the previous message and N and P go to the next and previous files, respectively, in multi-file output. With a numeric prefix argument, these commands move that many messages of files.
If you have an idea about any customization that would be handy but isn’t present in this list, please tell us! For info on how to reach us, see Bugs (known and unknown).
If this variable is set to any non-nil value,
‘cvs-mode-remove-handled’ will be called every time you check in
files, after the check-in is ready. See Removing handled entries.
If this variable is set to any non-nil value, directories that do
not contain any files to be checked in will not be listed in the
*cvs* buffer.
If this variable is set to any non-‘nil’ value any buffers you have that visit a file that is committed will be automatically reverted. This variable defaults to ‘t’. See Committing changes.
The ‘-u’ flag in the modules file can be used to run a command
whenever a ‘cvs update’ is performed (see cvs(5)). This regexp
is used to search for the last line in that output. It is normally set
to ‘$’. That setting is only correct if the command outputs
nothing. Note that PCL-CVS will get very confused if the command
outputs anything to stderr.
This variable can be set to override ‘CVSROOT’. It should be a
string. If it is set, then every time a cvs command is run, it
will be called as ‘cvs -d cvs-cvsroot…’. This can be
useful if your site has several repositories.
When you enter a log message by typing into the *cvs-commit-message* buffer, PCL-CVS normally automatically inserts a trailing newline, unless there already is one. This behavior can be controlled via ‘cvs-commit-buffer-require-final-newline’. If it is ‘t’ (the default behavior), a newline will always be appended. If it is ‘nil’, newlines will never be appended. Any other value causes PCL-CVS to ask the user whenever there is no trailing newline in the commit message buffer.
If this variable is non-nil, include full ChangeLog
paragraphs in the CVS log created by ‘cvs-mode-changelog-commit’.
This may be set in the local variables section of a ChangeLog
file, to indicate the policy for that ChangeLog.
A ChangeLog paragraph is a bunch of log text containing no blank lines; a paragraph usually describes a set of changes with a single purpose, but perhaps spanning several functions in several files. Changes in different paragraphs are unrelated.
You could argue that the CVS log entry for a file should contain the
full ChangeLog paragraph mentioning the change to the file, even though
it may mention other files, because that gives you the full context you
need to understand the change. This is the behavior you get when this
variable is set to t, the default.
On the other hand, you could argue that the CVS log entry for a change
should contain only the text for the changes which occurred in that
file, because the CVS log is per-file. This is the behavior you get
when this variable is set to nil.
If this variable is set to any non-‘nil’ value, the .cvsignore file will always be sorted whenever you use ‘cvs-mode-ignore’ to add a file to it. This option is on by default.
PCL-CVS adds a few extra features, including menus, mouse bindings, and fontification of the *cvs* buffer. The faces defined for fontification are listed below:
used to highlight directory changes.
Used to highlight file names.
Used to highlight the status of files which are ‘Unknown’.
Used to highlight the status of files which are handled and need no further action.
Used to highlight the status of files which still need action.
Used to highlight the marked file indicator (‘*’).
Used to highlight CVS messages.
If you find a bug or misfeature, don’t hesitate to tell us! Use M-x report-emacs-bug to send us a report. You can follow the same process for feature requests. We prefer discussing one thing at a time. If you find several unrelated bugs, please report them separately.
If you have problems using PCL-CVS or other questions, send them to the help-gnu-emacs mailing list. This is a good place to get help, as is the info-cvs list.
If you have ideas for improvements, or if you have written some extensions to this package, we would like to hear from you. We hope that you find this package useful!
Below is a partial list of currently known problems with PCL-CVS.
Unexpected output from CVS may confuse PCL-CVS. It will create warning messages in the *cvs* buffer alerting you to any parse errors. If you get these messages, please send a bug report to the email addresses listed above. Include the contents of the *cvs* buffer, the output of the CVS process (which should be found in the *cvs-tmp* buffer), and the versions of Emacs, PCL-CVS and CVS you are using.
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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.
This is an index of all the functions and variables documented in this manual.
This is an index of concepts discussed in this manual.
This index includes an entry for each PCL-CVS key sequence documented in this manual.