--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node Autorevert
+@section Auto Reverting non-file Buffers
+
+Normally Global Auto Revert Mode only reverts file buffers. There are
+two ways to auto-revert certain non-file buffers: enabling Auto Revert
+Mode in those buffers (using @kbd{M-x auto-revert-mode}) and setting
+@code{global-auto-revert-non-file-buffers} to @code{t}. The latter
+enables Auto Reverting for all types of buffers for which it is
+implemented, that is, for the types of buffers listed in the menu
+below.
+
+Like file buffers, non-file buffers should normally not revert while
+you are working on them, or while they contain information that might
+get lost after reverting. Therefore, they do not revert if they are
+``modified''. This can get tricky, because deciding when a non-file
+buffer should be marked modified is usually more difficult than for
+file buffers.
+
+Another tricky detail is that, for efficiency reasons, Auto Revert
+often does not try to detect all possible changes in the buffer, only
+changes that are ``major'' or easy to detect. Hence, enabling
+auto-reverting for a non-file buffer does not always guarantee that
+all information in the buffer is up to date and does not necessarily
+make manual reverts useless.
+
+At the other extreme, certain buffers automatically auto-revert every
+@code{auto-revert-interval} seconds. (This currently only applies to
+the Buffer Menu.) In this case, Auto Revert does not print any
+messages while reverting, even when @code{auto-revert-verbose} is
+non-@code{nil}.
+
+The details depend on the particular types of buffers and are
+explained in the corresponding sections.
+
+@menu
+* Auto Reverting the Buffer Menu::
+* Auto Reverting Dired::
+* Supporting additional buffers::
+@end menu
+
+@node Auto Reverting the Buffer Menu
+@subsection Auto Reverting the Buffer Menu
+
+If auto-reverting of non-file buffers is enabled, the Buffer Menu
+automatically reverts every @code{auto-revert-interval} seconds,
+whether there is a need for it or not. (It would probably take longer
+to check whether there is a need than to actually revert.)
+
+If the Buffer Menu inappropriately gets marked modified, just revert
+it manually using @kbd{g} and auto-reverting will resume. However, if
+you marked certain buffers to get deleted or to be displayed, you have
+to be careful, because reverting erases all marks. The fact that
+adding marks sets the buffer's modified flag prevents Auto Revert from
+automatically erasing the marks.
+
+@node Auto Reverting Dired
+@subsection Auto Reverting Dired buffers
+
+Auto-reverting Dired buffers currently works on GNU or Unix style
+operating systems. It may not work satisfactorily on some other
+systems.
+
+Dired buffers only auto-revert when the file list of the buffer's main
+directory changes. They do not auto-revert when information about a
+particular file changes or when inserted subdirectories change. To be
+sure that @emph{all} listed information is up to date, you have to
+manually revert using @kbd{g}, @emph{even} if auto-reverting is
+enabled in the Dired buffer. Sometimes, you might get the impression
+that modifying or saving files listed in the main directory actually
+does cause auto-reverting. This is because making changes to a file,
+or saving it, very often causes changes in the directory itself, for
+instance, through backup files or auto-save files. However, this is
+not guaranteed.
+
+If the Dired buffer is marked modified and there are no changes you
+want to protect, then most of the time you can make auto-reverting
+resume by manually reverting the buffer using @kbd{g}. There is one
+exception. If you flag or mark files, you can safely revert the
+buffer. This will not erase the flags or marks (unless the marked
+file has been deleted, of course). However, the buffer will stay
+modified, even after reverting, and auto-reverting will not resume.
+This is because, if you flag or mark files, you may be working on the
+buffer and you might not want the buffer to change without warning.
+If you want auto-reverting to resume in the presence of marks and
+flags, mark the buffer non-modified using @kbd{M-~}. However, adding,
+deleting or changing marks or flags will mark it modified again.
+
+Remote Dired buffers are not auto-reverted. Neither are Dired buffers
+for which you used shell wildcards or file arguments to list only some
+of the files. @samp{*Find*} and @samp{*Locate*} buffers do not
+auto-revert either.
+
+@node Supporting additional buffers
+@subsection Adding Support for Auto-Reverting additional Buffers.
+
+This section is intended for Elisp programmers who would like to add
+support for auto-reverting new types of buffers.
+
+To support auto-reverting the buffer must first of all have a
+@code{revert-buffer-function}. @xref{Definition of
+revert-buffer-function,, Reverting, elisp, the Emacs Lisp Reference Manual}.
+
+In addition, it @emph{must} have a @code{buffer-stale-function}.
+
+@defvar buffer-stale-function
+The value of this variable is a function to check whether a non-file
+buffer needs reverting. This should be a function with one optional
+argument @var{noconfirm}. The function should return non-@code{nil}
+if the buffer should be reverted. The buffer is current when this
+function is called.
+
+While this function is mainly intended for use in auto-reverting, it
+could be used for other purposes as well. For instance, if
+auto-reverting is not enabled, it could be used to warn the user that
+the buffer needs reverting. The idea behind the @var{noconfirm}
+argument is that it should be @code{t} if the buffer is going to be
+reverted without asking the user and @code{nil} if the function is
+just going to be used to warn the user that the buffer is out of date.
+In particular, for use in auto-reverting, @var{noconfirm} is @code{t}.
+If the function is only going to be used for auto-reverting, you can
+ignore the @var{noconfirm} argument.
+
+If you just want to automatically auto-revert every
+@code{auto-revert-interval} seconds, use:
+
+@example
+(set (make-local-variable 'buffer-stale-function)
+ #'(lambda (&optional noconfirm) 'fast))
+@end example
+
+@noindent
+in the buffer's mode function.
+
+The special return value @samp{fast} tells the caller that the need
+for reverting was not checked, but that reverting the buffer is fast.
+It also tells Auto Revert not to print any revert messages, even if
+@code{auto-revert-verbose} is non-@code{nil}. This is important, as
+getting revert messages every @code{auto-revert-interval} seconds can
+be very annoying. The information provided by this return value could
+also be useful if the function is consulted for purposes other than
+auto-reverting.
+@end defvar
+
+Once the buffer has a @code{revert-buffer-function} and a
+@code{buffer-stale-function}, several problems usually remain.
+
+The buffer will only auto-revert if it is marked unmodified. Hence,
+you will have to make sure that various functions mark the buffer
+modified if and only if either the buffer contains information that
+might be lost by reverting or there is reason to believe that the user
+might be inconvenienced by auto-reverting, because he is actively
+working on the buffer. The user can always override this by manually
+adjusting the modified status of the buffer. To support this, calling
+the @code{revert-buffer-function} on a buffer that is marked
+unmodified should always keep the buffer marked unmodified.
+
+It is important to assure that point does not continuously jump around
+as a consequence of auto-reverting. Of course, moving point might be
+inevitable if the buffer radically changes.
+
+You should make sure that the @code{revert-buffer-function} does not
+print messages that unnecessarily duplicate Auto Revert's own messages
+if @code{auto-revert-verbose} is @code{t} and effectively override a
+@code{nil} value for @code{auto-revert-verbose}. Hence, adapting a
+mode for auto-reverting often involves getting rid of such messages.
+This is especially important for buffers that automatically
+auto-revert every @code{auto-revert-interval} seconds.
+
+Also, you may want to update the documentation string of
+@code{global-auto-revert-non-file-buffers}.
+
+@ifinfo
+Finally, you should add a node to this chapter's menu. This node
+@end ifinfo
+@ifnotinfo
+Finally, you should add a section to this chapter. This section
+@end ifnotinfo
+should at the very least make clear whether enabling auto-reverting
+for the buffer reliably assures that all information in the buffer is
+completely up to date (or will be after @code{auto-revert-interval}
+seconds).
--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+
+@c Moved here from the Emacs Lisp Reference Manual, 2005-03-26.
+@node Advanced Calendar/Diary Usage
+@section Customizing the Calendar and Diary
+
+ There are many customizations that you can use to make the calendar and
+diary suit your personal tastes.
+
+@menu
+* Calendar Customizing:: Defaults you can set.
+* Holiday Customizing:: Defining your own holidays.
+* Date Display Format:: Changing the format.
+* Time Display Format:: Changing the format.
+* Diary Customizing:: Defaults you can set.
+* Hebrew/Islamic Entries:: How to obtain them.
+* Fancy Diary Display:: Enhancing the diary display, sorting entries,
+ using included diary files.
+* Sexp Diary Entries:: Fancy things you can do.
+@end menu
+
+@node Calendar Customizing
+@subsection Customizing the Calendar
+@vindex calendar-holiday-marker
+@vindex diary-entry-marker
+ The variable @code{calendar-holiday-marker} specifies how to mark a
+date as being a holiday. Its value may be a single-character string
+to insert next to the date, or a face name to use for displaying the
+date. Likewise, the variable @code{diary-entry-marker} specifies how
+to mark a date that has diary entries. The calendar creates faces
+named @code{holiday-face} and @code{diary-face} for these purposes;
+those symbols are the default values of these variables.
+
+@vindex calendar-load-hook
+ The variable @code{calendar-load-hook} is a normal hook run when the
+calendar package is first loaded (before actually starting to display
+the calendar).
+
+@vindex initial-calendar-window-hook
+ Starting the calendar runs the normal hook
+@code{initial-calendar-window-hook}. Recomputation of the calendar
+display does not run this hook. But if you leave the calendar with the
+@kbd{q} command and reenter it, the hook runs again.@refill
+
+@vindex today-visible-calendar-hook
+ The variable @code{today-visible-calendar-hook} is a normal hook run
+after the calendar buffer has been prepared with the calendar when the
+current date is visible in the window. One use of this hook is to
+replace today's date with asterisks; to do that, use the hook function
+@code{calendar-star-date}.
+
+@findex calendar-star-date
+@example
+(add-hook 'today-visible-calendar-hook 'calendar-star-date)
+@end example
+
+@noindent
+Another standard hook function marks the current date, either by
+changing its face or by adding an asterisk. Here's how to use it:
+
+@findex calendar-mark-today
+@example
+(add-hook 'today-visible-calendar-hook 'calendar-mark-today)
+@end example
+
+@noindent
+@vindex calendar-today-marker
+The variable @code{calendar-today-marker} specifies how to mark
+today's date. Its value should be a single-character string to insert
+next to the date or a face name to use for displaying the date. A
+face named @code{calendar-today-face} is provided for this purpose;
+that symbol is the default for this variable.
+
+@vindex today-invisible-calendar-hook
+@noindent
+ A similar normal hook, @code{today-invisible-calendar-hook} is run if
+the current date is @emph{not} visible in the window.
+
+@vindex calendar-move-hook
+ Each of the calendar cursor motion commands runs the hook
+@code{calendar-move-hook} after it moves the cursor.
+
+@node Holiday Customizing
+@subsection Customizing the Holidays
+
+@vindex calendar-holidays
+@vindex christian-holidays
+@vindex hebrew-holidays
+@vindex islamic-holidays
+ Emacs knows about holidays defined by entries on one of several lists.
+You can customize these lists of holidays to your own needs, adding or
+deleting holidays. The lists of holidays that Emacs uses are for
+general holidays (@code{general-holidays}), local holidays
+(@code{local-holidays}), Christian holidays (@code{christian-holidays}),
+Hebrew (Jewish) holidays (@code{hebrew-holidays}), Islamic (Muslim)
+holidays (@code{islamic-holidays}), and other holidays
+(@code{other-holidays}).
+
+@vindex general-holidays
+ The general holidays are, by default, holidays common throughout the
+United States. To eliminate these holidays, set @code{general-holidays}
+to @code{nil}.
+
+@vindex local-holidays
+ There are no default local holidays (but sites may supply some). You
+can set the variable @code{local-holidays} to any list of holidays, as
+described below.
+
+@vindex all-christian-calendar-holidays
+@vindex all-hebrew-calendar-holidays
+@vindex all-islamic-calendar-holidays
+ By default, Emacs does not include all the holidays of the religions
+that it knows, only those commonly found in secular calendars. For a
+more extensive collection of religious holidays, you can set any (or
+all) of the variables @code{all-christian-calendar-holidays},
+@code{all-hebrew-calendar-holidays}, or
+@code{all-islamic-calendar-holidays} to @code{t}. If you want to
+eliminate the religious holidays, set any or all of the corresponding
+variables @code{christian-holidays}, @code{hebrew-holidays}, and
+@code{islamic-holidays} to @code{nil}.@refill
+
+@vindex other-holidays
+ You can set the variable @code{other-holidays} to any list of
+holidays. This list, normally empty, is intended for individual use.
+
+@cindex holiday forms
+ Each of the lists (@code{general-holidays}, @code{local-holidays},
+@code{christian-holidays}, @code{hebrew-holidays},
+@code{islamic-holidays}, and @code{other-holidays}) is a list of
+@dfn{holiday forms}, each holiday form describing a holiday (or
+sometimes a list of holidays).
+
+ Here is a table of the possible kinds of holiday form. Day numbers
+and month numbers count starting from 1, but ``dayname'' numbers
+count Sunday as 0. The element @var{string} is always the
+name of the holiday, as a string.
+
+@table @code
+@item (holiday-fixed @var{month} @var{day} @var{string})
+A fixed date on the Gregorian calendar.
+
+@item (holiday-float @var{month} @var{dayname} @var{k} @var{string})
+The @var{k}th @var{dayname} in @var{month} on the Gregorian calendar
+(@var{dayname}=0 for Sunday, and so on); negative @var{k} means count back
+from the end of the month.
+
+@item (holiday-hebrew @var{month} @var{day} @var{string})
+A fixed date on the Hebrew calendar.
+
+@item (holiday-islamic @var{month} @var{day} @var{string})
+A fixed date on the Islamic calendar.
+
+@item (holiday-julian @var{month} @var{day} @var{string})
+A fixed date on the Julian calendar.
+
+@item (holiday-sexp @var{sexp} @var{string})
+A date calculated by the Lisp expression @var{sexp}. The expression
+should use the variable @code{year} to compute and return the date of a
+holiday, or @code{nil} if the holiday doesn't happen this year. The
+value of @var{sexp} must represent the date as a list of the form
+@code{(@var{month} @var{day} @var{year})}.
+
+@item (if @var{condition} @var{holiday-form})
+A holiday that happens only if @var{condition} is true.
+
+@item (@var{function} @r{[}@var{args}@r{]})
+A list of dates calculated by the function @var{function}, called with
+arguments @var{args}.
+@end table
+
+ For example, suppose you want to add Bastille Day, celebrated in
+France on July 14. You can do this as follows:
+
+@smallexample
+(setq other-holidays '((holiday-fixed 7 14 "Bastille Day")))
+@end smallexample
+
+@noindent
+The holiday form @code{(holiday-fixed 7 14 "Bastille Day")} specifies the
+fourteenth day of the seventh month (July).
+
+ Many holidays occur on a specific day of the week, at a specific time
+of month. Here is a holiday form describing Hurricane Supplication Day,
+celebrated in the Virgin Islands on the fourth Monday in August:
+
+@smallexample
+(holiday-float 8 1 4 "Hurricane Supplication Day")
+@end smallexample
+
+@noindent
+Here the 8 specifies August, the 1 specifies Monday (Sunday is 0,
+Tuesday is 2, and so on), and the 4 specifies the fourth occurrence in
+the month (1 specifies the first occurrence, 2 the second occurrence,
+@minus{}1 the last occurrence, @minus{}2 the second-to-last occurrence, and
+so on).
+
+ You can specify holidays that occur on fixed days of the Hebrew,
+Islamic, and Julian calendars too. For example,
+
+@smallexample
+(setq other-holidays
+ '((holiday-hebrew 10 2 "Last day of Hanukkah")
+ (holiday-islamic 3 12 "Mohammed's Birthday")
+ (holiday-julian 4 2 "Jefferson's Birthday")))
+@end smallexample
+
+@noindent
+adds the last day of Hanukkah (since the Hebrew months are numbered with
+1 starting from Nisan), the Islamic feast celebrating Mohammed's
+birthday (since the Islamic months are numbered from 1 starting with
+Muharram), and Thomas Jefferson's birthday, which is 2 April 1743 on the
+Julian calendar.
+
+ To include a holiday conditionally, use either Emacs Lisp's @code{if} or the
+@code{holiday-sexp} form. For example, American presidential elections
+occur on the first Tuesday after the first Monday in November of years
+divisible by 4:
+
+@smallexample
+(holiday-sexp '(if (= 0 (% year 4))
+ (calendar-gregorian-from-absolute
+ (1+ (calendar-dayname-on-or-before
+ 1 (+ 6 (calendar-absolute-from-gregorian
+ (list 11 1 year)))))))
+ "US Presidential Election")
+@end smallexample
+
+@noindent
+or
+
+@smallexample
+(if (= 0 (% displayed-year 4))
+ (fixed 11
+ (extract-calendar-day
+ (calendar-gregorian-from-absolute
+ (1+ (calendar-dayname-on-or-before
+ 1 (+ 6 (calendar-absolute-from-gregorian
+ (list 11 1 displayed-year)))))))
+ "US Presidential Election"))
+@end smallexample
+
+ Some holidays just don't fit into any of these forms because special
+calculations are involved in their determination. In such cases you
+must write a Lisp function to do the calculation. To include eclipses,
+for example, add @code{(eclipses)} to @code{other-holidays}
+and write an Emacs Lisp function @code{eclipses} that returns a
+(possibly empty) list of the relevant Gregorian dates among the range
+visible in the calendar window, with descriptive strings, like this:
+
+@smallexample
+(((6 27 1991) "Lunar Eclipse") ((7 11 1991) "Solar Eclipse") ... )
+@end smallexample
+
+@node Date Display Format
+@subsection Date Display Format
+@vindex calendar-date-display-form
+
+ You can customize the manner of displaying dates in the diary, in mode
+lines, and in messages by setting @code{calendar-date-display-form}.
+This variable holds a list of expressions that can involve the variables
+@code{month}, @code{day}, and @code{year}, which are all numbers in
+string form, and @code{monthname} and @code{dayname}, which are both
+alphabetic strings. In the American style, the default value of this
+list is as follows:
+
+@smallexample
+((if dayname (concat dayname ", ")) monthname " " day ", " year)
+@end smallexample
+
+@noindent
+while in the European style this value is the default:
+
+@smallexample
+((if dayname (concat dayname ", ")) day " " monthname " " year)
+@end smallexample
+
+@noindent
+The ISO standard date representation is this:
+
+@smallexample
+(year "-" month "-" day)
+@end smallexample
+
+@noindent
+This specifies a typical American format:
+
+@smallexample
+(month "/" day "/" (substring year -2))
+@end smallexample
+
+@node Time Display Format
+@subsection Time Display Format
+@vindex calendar-time-display-form
+
+ The calendar and diary by default display times of day in the
+conventional American style with the hours from 1 through 12, minutes,
+and either @samp{am} or @samp{pm}. If you prefer the European style,
+also known in the US as military, in which the hours go from 00 to 23,
+you can alter the variable @code{calendar-time-display-form}. This
+variable is a list of expressions that can involve the variables
+@code{12-hours}, @code{24-hours}, and @code{minutes}, which are all
+numbers in string form, and @code{am-pm} and @code{time-zone}, which are
+both alphabetic strings. The default value of
+@code{calendar-time-display-form} is as follows:
+
+@smallexample
+(12-hours ":" minutes am-pm
+ (if time-zone " (") time-zone (if time-zone ")"))
+@end smallexample
+
+@noindent
+Here is a value that provides European style times:
+
+@smallexample
+(24-hours ":" minutes
+ (if time-zone " (") time-zone (if time-zone ")"))
+@end smallexample
+
+@node Diary Customizing
+@subsection Customizing the Diary
+
+@vindex holidays-in-diary-buffer
+ Ordinarily, the mode line of the diary buffer window indicates any
+holidays that fall on the date of the diary entries. The process of
+checking for holidays can take several seconds, so including holiday
+information delays the display of the diary buffer noticeably. If you'd
+prefer to have a faster display of the diary buffer but without the
+holiday information, set the variable @code{holidays-in-diary-buffer} to
+@code{nil}.@refill
+
+@vindex number-of-diary-entries
+ The variable @code{number-of-diary-entries} controls the number of
+days of diary entries to be displayed at one time. It affects the
+initial display when @code{view-diary-entries-initially} is @code{t}, as
+well as the command @kbd{M-x diary}. For example, the default value is
+1, which says to display only the current day's diary entries. If the
+value is 2, both the current day's and the next day's entries are
+displayed. The value can also be a vector of seven elements: for
+example, if the value is @code{[0 2 2 2 2 4 1]} then no diary entries
+appear on Sunday, the current date's and the next day's diary entries
+appear Monday through Thursday, Friday through Monday's entries appear
+on Friday, while on Saturday only that day's entries appear.
+
+@vindex print-diary-entries-hook
+@findex print-diary-entries
+ The variable @code{print-diary-entries-hook} is a normal hook run
+after preparation of a temporary buffer containing just the diary
+entries currently visible in the diary buffer. (The other, irrelevant
+diary entries are really absent from the temporary buffer; in the diary
+buffer, they are merely hidden.) The default value of this hook does
+the printing with the command @code{lpr-buffer}. If you want to use a
+different command to do the printing, just change the value of this
+hook. Other uses might include, for example, rearranging the lines into
+order by day and time.
+
+@vindex diary-date-forms
+ You can customize the form of dates in your diary file, if neither the
+standard American nor European styles suits your needs, by setting the
+variable @code{diary-date-forms}. This variable is a list of patterns
+for recognizing a date. Each date pattern is a list whose elements may
+be regular expressions (@pxref{Regular Expressions,,, elisp, the Emacs
+Lisp Reference Manual}) or the symbols @code{month}, @code{day},
+@code{year}, @code{monthname}, and @code{dayname}. All these elements
+serve as patterns that match certain kinds of text in the diary file.
+In order for the date pattern, as a whole, to match, all of its elements
+must match consecutively.
+
+ A regular expression in a date pattern matches in its usual fashion,
+using the standard syntax table altered so that @samp{*} is a word
+constituent.
+
+ The symbols @code{month}, @code{day}, @code{year}, @code{monthname},
+and @code{dayname} match the month number, day number, year number,
+month name, and day name of the date being considered. The symbols that
+match numbers allow leading zeros; those that match names allow
+three-letter abbreviations and capitalization. All the symbols can
+match @samp{*}; since @samp{*} in a diary entry means ``any day'', ``any
+month'', and so on, it should match regardless of the date being
+considered.
+
+ The default value of @code{diary-date-forms} in the American style is
+this:
+
+@example
+((month "/" day "[^/0-9]")
+ (month "/" day "/" year "[^0-9]")
+ (monthname " *" day "[^,0-9]")
+ (monthname " *" day ", *" year "[^0-9]")
+ (dayname "\\W"))
+@end example
+
+ The date patterns in the list must be @emph{mutually exclusive} and
+must not match any portion of the diary entry itself, just the date and
+one character of whitespace. If, to be mutually exclusive, the pattern
+must match a portion of the diary entry text---beyond the whitespace
+that ends the date---then the first element of the date pattern
+@emph{must} be @code{backup}. This causes the date recognizer to back
+up to the beginning of the current word of the diary entry, after
+finishing the match. Even if you use @code{backup}, the date pattern
+must absolutely not match more than a portion of the first word of the
+diary entry. The default value of @code{diary-date-forms} in the
+European style is this list:
+
+@example
+((day "/" month "[^/0-9]")
+ (day "/" month "/" year "[^0-9]")
+ (backup day " *" monthname "\\W+\\<[^*0-9]")
+ (day " *" monthname " *" year "[^0-9]")
+ (dayname "\\W"))
+@end example
+
+@noindent
+Notice the use of @code{backup} in the third pattern, because it needs
+to match part of a word beyond the date itself to distinguish it from
+the fourth pattern.
+
+@node Hebrew/Islamic Entries
+@subsection Hebrew- and Islamic-Date Diary Entries
+
+ Your diary file can have entries based on Hebrew or Islamic dates, as
+well as entries based on the world-standard Gregorian calendar.
+However, because recognition of such entries is time-consuming and most
+people don't use them, you must explicitly enable their use. If you
+want the diary to recognize Hebrew-date diary entries, for example,
+you must do this:
+
+@vindex nongregorian-diary-listing-hook
+@vindex nongregorian-diary-marking-hook
+@findex list-hebrew-diary-entries
+@findex mark-hebrew-diary-entries
+@smallexample
+(add-hook 'nongregorian-diary-listing-hook 'list-hebrew-diary-entries)
+(add-hook 'nongregorian-diary-marking-hook 'mark-hebrew-diary-entries)
+@end smallexample
+
+@noindent
+If you want Islamic-date entries, do this:
+
+@findex list-islamic-diary-entries
+@findex mark-islamic-diary-entries
+@smallexample
+(add-hook 'nongregorian-diary-listing-hook 'list-islamic-diary-entries)
+(add-hook 'nongregorian-diary-marking-hook 'mark-islamic-diary-entries)
+@end smallexample
+
+ Hebrew- and Islamic-date diary entries have the same formats as
+Gregorian-date diary entries, except that @samp{H} precedes a Hebrew
+date and @samp{I} precedes an Islamic date. Moreover, because the
+Hebrew and Islamic month names are not uniquely specified by the first
+three letters, you may not abbreviate them. For example, a diary entry
+for the Hebrew date Heshvan 25 could look like this:
+
+@smallexample
+HHeshvan 25 Happy Hebrew birthday!
+@end smallexample
+
+@noindent
+and would appear in the diary for any date that corresponds to Heshvan 25
+on the Hebrew calendar. And here is an Islamic-date diary entry that matches
+Dhu al-Qada 25:
+
+@smallexample
+IDhu al-Qada 25 Happy Islamic birthday!
+@end smallexample
+
+ As with Gregorian-date diary entries, Hebrew- and Islamic-date entries
+are nonmarking if they are preceded with an ampersand (@samp{&}).
+
+ Here is a table of commands used in the calendar to create diary entries
+that match the selected date and other dates that are similar in the Hebrew
+or Islamic calendar:
+
+@table @kbd
+@item i h d
+Add a diary entry for the Hebrew date corresponding to the selected date
+(@code{insert-hebrew-diary-entry}).
+@item i h m
+Add a diary entry for the day of the Hebrew month corresponding to the
+selected date (@code{insert-monthly-hebrew-diary-entry}). This diary
+entry matches any date that has the same Hebrew day-within-month as the
+selected date.
+@item i h y
+Add a diary entry for the day of the Hebrew year corresponding to the
+selected date (@code{insert-yearly-hebrew-diary-entry}). This diary
+entry matches any date which has the same Hebrew month and day-within-month
+as the selected date.
+@item i i d
+Add a diary entry for the Islamic date corresponding to the selected date
+(@code{insert-islamic-diary-entry}).
+@item i i m
+Add a diary entry for the day of the Islamic month corresponding to the
+selected date (@code{insert-monthly-islamic-diary-entry}).
+@item i i y
+Add a diary entry for the day of the Islamic year corresponding to the
+selected date (@code{insert-yearly-islamic-diary-entry}).
+@end table
+
+@findex insert-hebrew-diary-entry
+@findex insert-monthly-hebrew-diary-entry
+@findex insert-yearly-hebrew-diary-entry
+@findex insert-islamic-diary-entry
+@findex insert-monthly-islamic-diary-entry
+@findex insert-yearly-islamic-diary-entry
+ These commands work much like the corresponding commands for ordinary
+diary entries: they apply to the date that point is on in the calendar
+window, and what they do is insert just the date portion of a diary entry
+at the end of your diary file. You must then insert the rest of the
+diary entry.
+
+@node Fancy Diary Display
+@subsection Fancy Diary Display
+@vindex diary-display-hook
+@findex simple-diary-display
+
+ Diary display works by preparing the diary buffer and then running the
+hook @code{diary-display-hook}. The default value of this hook
+(@code{simple-diary-display}) hides the irrelevant diary entries and
+then displays the buffer. However, if you specify the hook as follows,
+
+@cindex diary buffer
+@findex fancy-diary-display
+@example
+(add-hook 'diary-display-hook 'fancy-diary-display)
+@end example
+
+@noindent
+this enables fancy diary display. It displays diary entries and
+holidays by copying them into a special buffer that exists only for the
+sake of display. Copying to a separate buffer provides an opportunity
+to change the displayed text to make it prettier---for example, to sort
+the entries by the dates they apply to.
+
+ As with simple diary display, you can print a hard copy of the buffer
+with @code{print-diary-entries}. To print a hard copy of a day-by-day
+diary for a week, position point on Sunday of that week, type
+@kbd{7 d}, and then do @kbd{M-x print-diary-entries}. As usual, the
+inclusion of the holidays slows down the display slightly; you can speed
+things up by setting the variable @code{holidays-in-diary-buffer} to
+@code{nil}.
+
+@vindex diary-list-include-blanks
+ Ordinarily, the fancy diary buffer does not show days for which there are
+no diary entries, even if that day is a holiday. If you want such days to be
+shown in the fancy diary buffer, set the variable
+@code{diary-list-include-blanks} to @code{t}.@refill
+
+@cindex sorting diary entries
+ If you use the fancy diary display, you can use the normal hook
+@code{list-diary-entries-hook} to sort each day's diary entries by their
+time of day. Here's how:
+
+@findex sort-diary-entries
+@example
+(add-hook 'list-diary-entries-hook 'sort-diary-entries t)
+@end example
+
+@noindent
+For each day, this sorts diary entries that begin with a recognizable
+time of day according to their times. Diary entries without times come
+first within each day.
+
+ Fancy diary display also has the ability to process included diary
+files. This permits a group of people to share a diary file for events
+that apply to all of them. Lines in the diary file of this form:
+
+@smallexample
+#include "@var{filename}"
+@end smallexample
+
+@noindent
+includes the diary entries from the file @var{filename} in the fancy
+diary buffer. The include mechanism is recursive, so that included files
+can include other files, and so on; you must be careful not to have a
+cycle of inclusions, of course. Here is how to enable the include
+facility:
+
+@vindex list-diary-entries-hook
+@vindex mark-diary-entries-hook
+@findex include-other-diary-files
+@findex mark-included-diary-files
+@smallexample
+(add-hook 'list-diary-entries-hook 'include-other-diary-files)
+(add-hook 'mark-diary-entries-hook 'mark-included-diary-files)
+@end smallexample
+
+The include mechanism works only with the fancy diary display, because
+ordinary diary display shows the entries directly from your diary file.
+
+@node Sexp Diary Entries
+@subsection Sexp Entries and the Fancy Diary Display
+@cindex sexp diary entries
+
+ Sexp diary entries allow you to do more than just have complicated
+conditions under which a diary entry applies. If you use the fancy
+diary display, sexp entries can generate the text of the entry depending
+on the date itself. For example, an anniversary diary entry can insert
+the number of years since the anniversary date into the text of the
+diary entry. Thus the @samp{%d} in this dairy entry:
+
+@findex diary-anniversary
+@smallexample
+%%(diary-anniversary 10 31 1948) Arthur's birthday (%d years old)
+@end smallexample
+
+@noindent
+gets replaced by the age, so on October 31, 1990 the entry appears in
+the fancy diary buffer like this:
+
+@smallexample
+Arthur's birthday (42 years old)
+@end smallexample
+
+@noindent
+If the diary file instead contains this entry:
+
+@smallexample
+%%(diary-anniversary 10 31 1948) Arthur's %d%s birthday
+@end smallexample
+
+@noindent
+the entry in the fancy diary buffer for October 31, 1990 appears like this:
+
+@smallexample
+Arthur's 42nd birthday
+@end smallexample
+
+ Similarly, cyclic diary entries can interpolate the number of repetitions
+that have occurred:
+
+@findex diary-cyclic
+@smallexample
+%%(diary-cyclic 50 1 1 1990) Renew medication (%d%s time)
+@end smallexample
+
+@noindent
+looks like this:
+
+@smallexample
+Renew medication (5th time)
+@end smallexample
+
+@noindent
+in the fancy diary display on September 8, 1990.
+
+ There is an early reminder diary sexp that includes its entry in the
+diary not only on the date of occurrence, but also on earlier dates.
+For example, if you want a reminder a week before your anniversary, you
+can use
+
+@findex diary-remind
+@smallexample
+%%(diary-remind '(diary-anniversary 12 22 1968) 7) Ed's anniversary
+@end smallexample
+
+@noindent
+and the fancy diary will show
+@smallexample
+Ed's anniversary
+@end smallexample
+@noindent
+both on December 15 and on December 22.
+
+@findex diary-date
+ The function @code{diary-date} applies to dates described by a month,
+day, year combination, each of which can be an integer, a list of
+integers, or @code{t}. The value @code{t} means all values. For
+example,
+
+@smallexample
+%%(diary-date '(10 11 12) 22 t) Rake leaves
+@end smallexample
+
+@noindent
+causes the fancy diary to show
+
+@smallexample
+Rake leaves
+@end smallexample
+
+@noindent
+on October 22, November 22, and December 22 of every year.
+
+@findex diary-float
+ The function @code{diary-float} allows you to describe diary entries
+that apply to dates like the third Friday of November, or the last
+Tuesday in April. The parameters are the @var{month}, @var{dayname},
+and an index @var{n}. The entry appears on the @var{n}th @var{dayname}
+of @var{month}, where @var{dayname}=0 means Sunday, 1 means Monday, and
+so on. If @var{n} is negative it counts backward from the end of
+@var{month}. The value of @var{month} can be a list of months, a single
+month, or @code{t} to specify all months. You can also use an optional
+parameter @var{day} to specify the @var{n}th @var{dayname} of
+@var{month} on or after/before @var{day}; the value of @var{day} defaults
+to 1 if @var{n} is positive and to the last day of @var{month} if
+@var{n} is negative. For example,
+
+@smallexample
+%%(diary-float t 1 -1) Pay rent
+@end smallexample
+
+@noindent
+causes the fancy diary to show
+
+@smallexample
+Pay rent
+@end smallexample
+
+@noindent
+on the last Monday of every month.
+
+ The generality of sexp diary entries lets you specify any diary
+entry that you can describe algorithmically. A sexp diary entry
+contains an expression that computes whether the entry applies to any
+given date. If its value is non-@code{nil}, the entry applies to that
+date; otherwise, it does not. The expression can use the variable
+@code{date} to find the date being considered; its value is a list
+(@var{month} @var{day} @var{year}) that refers to the Gregorian
+calendar.
+
+ The sexp diary entry applies to a date when the expression's value
+is non-@code{nil}, but some values have more specific meanings. If
+the value is a string, that string is a description of the event which
+occurs on that date. The value can also have the form
+@code{(@var{mark} . @var{string})}; then @var{mark} specifies how to
+mark the date in the calendar, and @var{string} is the description of
+the event. If @var{mark} is a single-character string, that character
+appears next to the date in the calendar. If @var{mark} is a face
+name, the date is displayed in that face. If @var{mark} is
+@code{nil}, that specifies no particular highlighting for the date.
+
+ Suppose you get paid on the 21st of the month if it is a weekday, and
+on the Friday before if the 21st is on a weekend. Here is how to write
+a sexp diary entry that matches those dates:
+
+@smallexample
+&%%(let ((dayname (calendar-day-of-week date))
+ (day (car (cdr date))))
+ (or (and (= day 21) (memq dayname '(1 2 3 4 5)))
+ (and (memq day '(19 20)) (= dayname 5)))
+ ) Pay check deposited
+@end smallexample
+
+ The following sexp diary entries take advantage of the ability (in the fancy
+diary display) to concoct diary entries whose text varies based on the date:
+
+@findex diary-sunrise-sunset
+@findex diary-phases-of-moon
+@findex diary-day-of-year
+@findex diary-iso-date
+@findex diary-julian-date
+@findex diary-astro-day-number
+@findex diary-hebrew-date
+@findex diary-islamic-date
+@findex diary-french-date
+@findex diary-mayan-date
+@table @code
+@item %%(diary-sunrise-sunset)
+Make a diary entry for the local times of today's sunrise and sunset.
+@item %%(diary-phases-of-moon)
+Make a diary entry for the phases (quarters) of the moon.
+@item %%(diary-day-of-year)
+Make a diary entry with today's day number in the current year and the number
+of days remaining in the current year.
+@item %%(diary-iso-date)
+Make a diary entry with today's equivalent ISO commercial date.
+@item %%(diary-julian-date)
+Make a diary entry with today's equivalent date on the Julian calendar.
+@item %%(diary-astro-day-number)
+Make a diary entry with today's equivalent astronomical (Julian) day number.
+@item %%(diary-hebrew-date)
+Make a diary entry with today's equivalent date on the Hebrew calendar.
+@item %%(diary-islamic-date)
+Make a diary entry with today's equivalent date on the Islamic calendar.
+@item %%(diary-french-date)
+Make a diary entry with today's equivalent date on the French Revolutionary
+calendar.
+@item %%(diary-mayan-date)
+Make a diary entry with today's equivalent date on the Mayan calendar.
+@end table
+
+@noindent
+Thus including the diary entry
+
+@example
+&%%(diary-hebrew-date)
+@end example
+
+@noindent
+causes every day's diary display to contain the equivalent date on the
+Hebrew calendar, if you are using the fancy diary display. (With simple
+diary display, the line @samp{&%%(diary-hebrew-date)} appears in the
+diary for any date, but does nothing particularly useful.)
+
+ These functions can be used to construct sexp diary entries based on
+the Hebrew calendar in certain standard ways:
+
+@cindex rosh hodesh
+@findex diary-rosh-hodesh
+@cindex parasha, weekly
+@findex diary-parasha
+@cindex candle lighting times
+@findex diary-sabbath-candles
+@cindex omer count
+@findex diary-omer
+@cindex yahrzeits
+@findex diary-yahrzeit
+@table @code
+@item %%(diary-rosh-hodesh)
+Make a diary entry that tells the occurrence and ritual announcement of each
+new Hebrew month.
+@item %%(diary-parasha)
+Make a Saturday diary entry that tells the weekly synagogue scripture reading.
+@item %%(diary-sabbath-candles)
+Make a Friday diary entry that tells the @emph{local time} of Sabbath
+candle lighting.
+@item %%(diary-omer)
+Make a diary entry that gives the omer count, when appropriate.
+@item %%(diary-yahrzeit @var{month} @var{day} @var{year}) @var{name}
+Make a diary entry marking the anniversary of a date of death. The date
+is the @emph{Gregorian} (civil) date of death. The diary entry appears
+on the proper Hebrew calendar anniversary and on the day before. (In
+the European style, the order of the parameters is changed to @var{day},
+@var{month}, @var{year}.)
+@end table
+
+ All the functions documented above take an optional argument
+@var{mark} which specifies how to mark the date in the calendar display.
+If one of these functions decides that it applies to a certain date,
+it returns a value that contains @var{mark}.
--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node Subdir Switches
+@section Subdirectory Switches in Dired
+
+You can insert subdirectories with specified @code{ls} switches in
+Dired buffers, using @kbd{C-u i}. You can change the @code{ls}
+switches of an already inserted subdirectory using @kbd{C-u l}.
+
+In Emacs versions 22.1 and later, Dired remembers the switches, so
+that reverting the buffer will not change them back to the main
+directory's switches. Deleting a subdirectory forgets about its
+switches.
+
+Using @code{dired-undo} (usually bound to @kbd{C-_} and @kbd{C-x u})
+to reinsert or delete subdirectories, that were inserted with explicit
+switches, can bypass Dired's machinery for remembering (or forgetting)
+switches. Deleting a subdirectory using @code{dired-undo} does not
+forget its switches. When later reinserted using @kbd{i}, it will be
+reinserted using its old switches. Using @code{dired-undo} to
+reinsert a subdirectory that was deleted using the regular
+Dired commands (not @code{dired-undo}) will originally insert it with
+its old switches. However, reverting the buffer will relist it using
+the buffer's default switches. If any of this yields problems, you
+can easily correct the situation using @kbd{C-u i} or @kbd{C-u l}.
+
+Dired does not remember the @code{R} switch. Inserting a subdirectory
+with switches that include the @code{R} switch is equivalent with
+inserting each of its subdirectories using all remaining switches.
+For instance, updating or killing a subdirectory that was inserted
+with the @code{R} switch will not update or kill its subdirectories.
+
+The buffer's default switches do not affect subdirectories that were
+inserted using explicitly specified switches. In particular,
+commands such as @kbd{s}, that change the buffer's switches do not
+affect such subdirectories. (They do affect subdirectories without
+explicitly assigned switches, however.)
+
+You can make Dired forget about all subdirectory switches and relist
+all subdirectories with the buffer's default switches using
+@kbd{M-x dired-reset-subdir-switches}. This also reverts the Dired buffer.
--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node Emerge
+@section Merging Files with Emerge
+@cindex Emerge
+@cindex merging files
+
+ It's not unusual for programmers to get their signals crossed and
+modify the same program in two different directions. To recover from
+this confusion, you need to merge the two versions. Emerge makes this
+easier. For other ways to compare files, see @ref{Comparing Files,,,
+emacs, the Emacs Manual} and @ref{Top, Ediff,, ediff, The Ediff
+Manual}.
+
+@menu
+* Overview of Emerge:: How to start Emerge. Basic concepts.
+* Submodes of Emerge:: Fast mode vs. Edit mode.
+ Skip Prefers mode and Auto Advance mode.
+* State of Difference:: You do the merge by specifying state A or B
+ for each difference.
+* Merge Commands:: Commands for selecting a difference,
+ changing states of differences, etc.
+* Exiting Emerge:: What to do when you've finished the merge.
+* Combining in Emerge:: How to keep both alternatives for a difference.
+* Fine Points of Emerge:: Misc.
+@end menu
+
+@node Overview of Emerge
+@subsection Overview of Emerge
+
+ To start Emerge, run one of these four commands:
+
+@table @kbd
+@item M-x emerge-files
+@findex emerge-files
+Merge two specified files.
+
+@item M-x emerge-files-with-ancestor
+@findex emerge-files-with-ancestor
+Merge two specified files, with reference to a common ancestor.
+
+@item M-x emerge-buffers
+@findex emerge-buffers
+Merge two buffers.
+
+@item M-x emerge-buffers-with-ancestor
+@findex emerge-buffers-with-ancestor
+Merge two buffers with reference to a common ancestor in a third
+buffer.
+@end table
+
+@cindex merge buffer (Emerge)
+@cindex A and B buffers (Emerge)
+ The Emerge commands compare two files or buffers, and display the
+comparison in three buffers: one for each input text (the @dfn{A buffer}
+and the @dfn{B buffer}), and one (the @dfn{merge buffer}) where merging
+takes place. The merge buffer shows the full merged text, not just the
+differences. Wherever the two input texts differ, you can choose which
+one of them to include in the merge buffer.
+
+ The Emerge commands that take input from existing buffers use only
+the accessible portions of those buffers, if they are narrowed.
+@xref{Narrowing,,, emacs, the Emacs Manual}.
+
+
+ If a common ancestor version is available, from which the two texts to
+be merged were both derived, Emerge can use it to guess which
+alternative is right. Wherever one current version agrees with the
+ancestor, Emerge presumes that the other current version is a deliberate
+change which should be kept in the merged version. Use the
+@samp{with-ancestor} commands if you want to specify a common ancestor
+text. These commands read three file or buffer names---variant A,
+variant B, and the common ancestor.
+
+ After the comparison is done and the buffers are prepared, the
+interactive merging starts. You control the merging by typing special
+@dfn{merge commands} in the merge buffer (@pxref{Merge Commands}).
+For each run of differences between the input texts, you can choose
+which one of them to keep, or edit them both together.
+
+ The merge buffer uses a special major mode, Emerge mode, with commands
+for making these choices. But you can also edit the buffer with
+ordinary Emacs commands.
+
+ At any given time, the attention of Emerge is focused on one
+particular difference, called the @dfn{selected} difference. This
+difference is marked off in the three buffers like this:
+
+@example
+vvvvvvvvvvvvvvvvvvvv
+@var{text that differs}
+^^^^^^^^^^^^^^^^^^^^
+@end example
+
+@noindent
+Emerge numbers all the differences sequentially and the mode
+line always shows the number of the selected difference.
+
+ Normally, the merge buffer starts out with the A version of the text.
+But when the A version of a difference agrees with the common ancestor,
+then the B version is initially preferred for that difference.
+
+ Emerge leaves the merged text in the merge buffer when you exit. At
+that point, you can save it in a file with @kbd{C-x C-w}. If you give a
+numeric argument to @code{emerge-files} or
+@code{emerge-files-with-ancestor}, it reads the name of the output file
+using the minibuffer. (This is the last file name those commands read.)
+Then exiting from Emerge saves the merged text in the output file.
+
+ Normally, Emerge commands save the output buffer in its file when you
+exit. If you abort Emerge with @kbd{C-]}, the Emerge command does not
+save the output buffer, but you can save it yourself if you wish.
+
+@node Submodes of Emerge
+@subsection Submodes of Emerge
+
+ You can choose between two modes for giving merge commands: Fast mode
+and Edit mode. In Fast mode, basic merge commands are single
+characters, but ordinary Emacs commands are disabled. This is
+convenient if you use only merge commands. In Edit mode, all merge
+commands start with the prefix key @kbd{C-c C-c}, and the normal Emacs
+commands are also available. This allows editing the merge buffer, but
+slows down Emerge operations.
+
+ Use @kbd{e} to switch to Edit mode, and @kbd{C-c C-c f} to switch to
+Fast mode. The mode line indicates Edit and Fast modes with @samp{E}
+and @samp{F}.
+
+ Emerge has two additional submodes that affect how particular merge
+commands work: Auto Advance mode and Skip Prefers mode.
+
+ If Auto Advance mode is in effect, the @kbd{a} and @kbd{b} commands
+advance to the next difference. This lets you go through the merge
+faster as long as you simply choose one of the alternatives from the
+input. The mode line indicates Auto Advance mode with @samp{A}.
+
+ If Skip Prefers mode is in effect, the @kbd{n} and @kbd{p} commands
+skip over differences in states prefer-A and prefer-B (@pxref{State of
+Difference}). Thus you see only differences for which neither version
+is presumed ``correct.'' The mode line indicates Skip Prefers mode with
+@samp{S}.
+
+@findex emerge-auto-advance-mode
+@findex emerge-skip-prefers-mode
+ Use the command @kbd{s a} (@code{emerge-auto-advance-mode}) to set or
+clear Auto Advance mode. Use @kbd{s s}
+(@code{emerge-skip-prefers-mode}) to set or clear Skip Prefers mode.
+These commands turn on the mode with a positive argument, turns it off
+with a negative or zero argument, and toggle the mode with no argument.
+
+@node State of Difference
+@subsection State of a Difference
+
+ In the merge buffer, a difference is marked with lines of @samp{v} and
+@samp{^} characters. Each difference has one of these seven states:
+
+@table @asis
+@item A
+The difference is showing the A version. The @kbd{a} command always
+produces this state; the mode line indicates it with @samp{A}.
+
+@item B
+The difference is showing the B version. The @kbd{b} command always
+produces this state; the mode line indicates it with @samp{B}.
+
+@item default-A
+@itemx default-B
+The difference is showing the A or the B state by default, because you
+haven't made a choice. All differences start in the default-A state
+(and thus the merge buffer is a copy of the A buffer), except those for
+which one alternative is ``preferred'' (see below).
+
+When you select a difference, its state changes from default-A or
+default-B to plain A or B. Thus, the selected difference never has
+state default-A or default-B, and these states are never displayed in
+the mode line.
+
+The command @kbd{d a} chooses default-A as the default state, and @kbd{d
+b} chooses default-B. This chosen default applies to all differences
+which you haven't ever selected and for which no alternative is preferred.
+If you are moving through the merge sequentially, the differences you
+haven't selected are those following the selected one. Thus, while
+moving sequentially, you can effectively make the A version the default
+for some sections of the merge buffer and the B version the default for
+others by using @kbd{d a} and @kbd{d b} between sections.
+
+@item prefer-A
+@itemx prefer-B
+The difference is showing the A or B state because it is
+@dfn{preferred}. This means that you haven't made an explicit choice,
+but one alternative seems likely to be right because the other
+alternative agrees with the common ancestor. Thus, where the A buffer
+agrees with the common ancestor, the B version is preferred, because
+chances are it is the one that was actually changed.
+
+These two states are displayed in the mode line as @samp{A*} and @samp{B*}.
+
+@item combined
+The difference is showing a combination of the A and B states, as a
+result of the @kbd{x c} or @kbd{x C} commands.
+
+Once a difference is in this state, the @kbd{a} and @kbd{b} commands
+don't do anything to it unless you give them a numeric argument.
+
+The mode line displays this state as @samp{comb}.
+@end table
+
+@node Merge Commands
+@subsection Merge Commands
+
+ Here are the Merge commands for Fast mode; in Edit mode, precede them
+with @kbd{C-c C-c}:
+
+@table @kbd
+@item p
+Select the previous difference.
+
+@item n
+Select the next difference.
+
+@item a
+Choose the A version of this difference.
+
+@item b
+Choose the B version of this difference.
+
+@item C-u @var{n} j
+Select difference number @var{n}.
+
+@item .
+Select the difference containing point. You can use this command in the
+merge buffer or in the A or B buffer.
+
+@item q
+Quit---finish the merge.
+
+@item C-]
+Abort---exit merging and do not save the output.
+
+@item f
+Go into Fast mode. (In Edit mode, this is actually @kbd{C-c C-c f}.)
+
+@item e
+Go into Edit mode.
+
+@item l
+Recenter (like @kbd{C-l}) all three windows.
+
+@item -
+Specify part of a prefix numeric argument.
+
+@item @var{digit}
+Also specify part of a prefix numeric argument.
+
+@item d a
+Choose the A version as the default from here down in
+the merge buffer.
+
+@item d b
+Choose the B version as the default from here down in
+the merge buffer.
+
+@item c a
+Copy the A version of this difference into the kill ring.
+
+@item c b
+Copy the B version of this difference into the kill ring.
+
+@item i a
+Insert the A version of this difference at point.
+
+@item i b
+Insert the B version of this difference at point.
+
+@item m
+Put point and mark around the difference.
+
+@item ^
+Scroll all three windows down (like @kbd{M-v}).
+
+@item v
+Scroll all three windows up (like @kbd{C-v}).
+
+@item <
+Scroll all three windows left (like @kbd{C-x <}).
+
+@item >
+Scroll all three windows right (like @kbd{C-x >}).
+
+@item |
+Reset horizontal scroll on all three windows.
+
+@item x 1
+Shrink the merge window to one line. (Use @kbd{C-u l} to restore it
+to full size.)
+
+@item x c
+Combine the two versions of this difference (@pxref{Combining in
+Emerge}).
+
+@item x f
+Show the names of the files/buffers Emerge is operating on, in a Help
+window. (Use @kbd{C-u l} to restore windows.)
+
+@item x j
+Join this difference with the following one.
+(@kbd{C-u x j} joins this difference with the previous one.)
+
+@item x s
+Split this difference into two differences. Before you use this
+command, position point in each of the three buffers at the place where
+you want to split the difference.
+
+@item x t
+Trim identical lines off the top and bottom of the difference.
+Such lines occur when the A and B versions are
+identical but differ from the ancestor version.
+@end table
+
+@node Exiting Emerge
+@subsection Exiting Emerge
+
+ The @kbd{q} command (@code{emerge-quit}) finishes the merge, storing
+the results into the output file if you specified one. It restores the
+A and B buffers to their proper contents, or kills them if they were
+created by Emerge and you haven't changed them. It also disables the
+Emerge commands in the merge buffer, since executing them later could
+damage the contents of the various buffers.
+
+ @kbd{C-]} aborts the merge. This means exiting without writing the
+output file. If you didn't specify an output file, then there is no
+real difference between aborting and finishing the merge.
+
+ If the Emerge command was called from another Lisp program, then its
+return value is @code{t} for successful completion, or @code{nil} if you
+abort.
+
+@node Combining in Emerge
+@subsection Combining the Two Versions
+
+ Sometimes you want to keep @emph{both} alternatives for a particular
+difference. To do this, use @kbd{x c}, which edits the merge buffer
+like this:
+
+@example
+@group
+#ifdef NEW
+@var{version from A buffer}
+#else /* not NEW */
+@var{version from B buffer}
+#endif /* not NEW */
+@end group
+@end example
+
+@noindent
+@vindex emerge-combine-versions-template
+While this example shows C preprocessor conditionals delimiting the two
+alternative versions, you can specify the strings to use by setting
+the variable @code{emerge-combine-versions-template} to a string of your
+choice. In the string, @samp{%a} says where to put version A, and
+@samp{%b} says where to put version B. The default setting, which
+produces the results shown above, looks like this:
+
+@example
+@group
+"#ifdef NEW\n%a#else /* not NEW */\n%b#endif /* not NEW */\n"
+@end group
+@end example
+
+@node Fine Points of Emerge
+@subsection Fine Points of Emerge
+
+ During the merge, you mustn't try to edit the A and B buffers yourself.
+Emerge modifies them temporarily, but ultimately puts them back the way
+they were.
+
+ You can have any number of merges going at once---just don't use any one
+buffer as input to more than one merge at once, since the temporary
+changes made in these buffers would get in each other's way.
+
+ Starting Emerge can take a long time because it needs to compare the
+files fully. Emacs can't do anything else until @code{diff} finishes.
+Perhaps in the future someone will change Emerge to do the comparison in
+the background when the input files are large---then you could keep on
+doing other things with Emacs until Emerge is ready to accept
+commands.
+
+@vindex emerge-startup-hook
+ After setting up the merge, Emerge runs the hook
+@code{emerge-startup-hook}. @xref{Hooks,,, emacs, the Emacs Manual}.
--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node Fortran
+@section Fortran Mode
+@cindex Fortran mode
+@cindex mode, Fortran
+
+ Fortran mode provides special motion commands for Fortran statements
+and subprograms, and indentation commands that understand Fortran
+conventions of nesting, line numbers and continuation statements.
+Fortran mode has support for Auto Fill mode that breaks long lines into
+proper Fortran continuation lines.
+
+ Special commands for comments are provided because Fortran comments
+are unlike those of other languages. Built-in abbrevs optionally save
+typing when you insert Fortran keywords.
+
+ Use @kbd{M-x fortran-mode} to switch to this major mode. This
+command runs the hook @code{fortran-mode-hook}. @xref{Hooks,,, emacs,
+the Emacs Manual}.
+
+@cindex Fortran77 and Fortran90
+@findex f90-mode
+@findex fortran-mode
+ Fortran mode is meant for editing Fortran77 ``fixed format'' (and also
+``tab format'') source code. For editing the modern Fortran90 or
+Fortran95 ``free format'' source code, use F90 mode (@code{f90-mode}).
+Emacs normally uses Fortran mode for files with extension @samp{.f},
+@samp{.F} or @samp{.for}, and F90 mode for the extension @samp{.f90} and
+@samp{.f95}. GNU Fortran supports both kinds of format.
+
+@menu
+* Motion: Fortran Motion. Moving point by statements or subprograms.
+* Indent: Fortran Indent. Indentation commands for Fortran.
+* Comments: Fortran Comments. Inserting and aligning comments.
+* Autofill: Fortran Autofill. Auto fill support for Fortran.
+* Columns: Fortran Columns. Measuring columns for valid Fortran.
+* Abbrev: Fortran Abbrev. Built-in abbrevs for Fortran keywords.
+@end menu
+
+@node Fortran Motion
+@subsection Motion Commands
+
+ In addition to the normal commands for moving by and operating on
+``defuns'' (Fortran subprograms---functions and subroutines, as well as
+modules for F90 mode), Fortran mode provides special commands to move by
+statements and other program units.
+
+@table @kbd
+@kindex C-c C-n @r{(Fortran mode)}
+@findex fortran-next-statement
+@findex f90-next-statement
+@item C-c C-n
+Move to the beginning of the next statement
+(@code{fortran-next-statement}/@code{f90-next-statement}).
+
+@kindex C-c C-p @r{(Fortran mode)}
+@findex fortran-previous-statement
+@findex f90-previous-statement
+@item C-c C-p
+Move to the beginning of the previous statement
+(@code{fortran-previous-statement}/@code{f90-previous-statement}).
+If there is no previous statement (i.e. if called from the first
+statement in the buffer), move to the start of the buffer.
+
+@kindex C-c C-e @r{(F90 mode)}
+@findex f90-next-block
+@item C-c C-e
+Move point forward to the start of the next code block
+(@code{f90-next-block}). A code block is a subroutine,
+@code{if}--@code{endif} statement, and so forth. This command exists
+for F90 mode only, not Fortran mode. With a numeric argument, this
+moves forward that many blocks.
+
+@kindex C-c C-a @r{(F90 mode)}
+@findex f90-previous-block
+@item C-c C-a
+Move point backward to the previous code block
+(@code{f90-previous-block}). This is like @code{f90-next-block}, but
+moves backwards.
+
+@kindex C-M-n @r{(Fortran mode)}
+@findex fortran-end-of-block
+@findex f90-end-of-block
+@item C-M-n
+Move to the end of the current code block
+(@code{fortran-end-of-block}/@code{f90-end-of-block}). With a numeric
+agument, move forward that number of blocks. The mark is set before
+moving point. The F90 mode version of this command checks for
+consistency of block types and labels (if present), but it does not
+check the outermost block since that may be incomplete.
+
+@kindex C-M-p @r{(Fortran mode)}
+@findex fortran-beginning-of-block
+@findex f90-beginning-of-block
+@item C-M-p
+Move to the start of the current code block
+(@code{fortran-beginning-of-block}/@code{f90-beginning-of-block}). This
+is like @code{fortran-end-of-block}, but moves backwards.
+@end table
+
+@node Fortran Indent
+@subsection Fortran Indentation
+
+ Special commands and features are needed for indenting Fortran code in
+order to make sure various syntactic entities (line numbers, comment line
+indicators and continuation line flags) appear in the columns that are
+required for standard, fixed (or tab) format Fortran.
+
+@menu
+* Commands: ForIndent Commands. Commands for indenting and filling Fortran.
+* Contline: ForIndent Cont. How continuation lines indent.
+* Numbers: ForIndent Num. How line numbers auto-indent.
+* Conv: ForIndent Conv. Conventions you must obey to avoid trouble.
+* Vars: ForIndent Vars. Variables controlling Fortran indent style.
+@end menu
+
+@node ForIndent Commands
+@subsubsection Fortran Indentation and Filling Commands
+
+@table @kbd
+@item C-M-j
+Break the current line at point and set up a continuation line
+(@code{fortran-split-line}).
+@item M-^
+Join this line to the previous line (@code{fortran-join-line}).
+@item C-M-q
+Indent all the lines of the subprogram point is in
+(@code{fortran-indent-subprogram}).
+@item M-q
+Fill a comment block or statement.
+@end table
+
+@kindex C-M-q @r{(Fortran mode)}
+@findex fortran-indent-subprogram
+ The key @kbd{C-M-q} runs @code{fortran-indent-subprogram}, a command
+to reindent all the lines of the Fortran subprogram (function or
+subroutine) containing point.
+
+@kindex C-M-j @r{(Fortran mode)}
+@findex fortran-split-line
+ The key @kbd{C-M-j} runs @code{fortran-split-line}, which splits
+a line in the appropriate fashion for Fortran. In a non-comment line,
+the second half becomes a continuation line and is indented
+accordingly. In a comment line, both halves become separate comment
+lines.
+
+@kindex M-^ @r{(Fortran mode)}
+@kindex C-c C-d @r{(Fortran mode)}
+@findex fortran-join-line
+ @kbd{M-^} or @kbd{C-c C-d} runs the command @code{fortran-join-line},
+which joins a continuation line back to the previous line, roughly as
+the inverse of @code{fortran-split-line}. The point must be on a
+continuation line when this command is invoked.
+
+@kindex M-q @r{(Fortran mode)}
+@kbd{M-q} in Fortran mode fills the comment block or statement that
+point is in. This removes any excess statement continuations.
+
+@node ForIndent Cont
+@subsubsection Continuation Lines
+@cindex Fortran continuation lines
+
+@vindex fortran-continuation-string
+ Most Fortran77 compilers allow two ways of writing continuation lines.
+If the first non-space character on a line is in column 5, then that
+line is a continuation of the previous line. We call this @dfn{fixed
+format}. (In GNU Emacs we always count columns from 0; but note that
+the Fortran standard counts from 1.) The variable
+@code{fortran-continuation-string} specifies what character to put in
+column 5. A line that starts with a tab character followed by any digit
+except @samp{0} is also a continuation line. We call this style of
+continuation @dfn{tab format}. (Fortran90 introduced ``free format'',
+with another style of continuation lines).
+
+@vindex indent-tabs-mode @r{(Fortran mode)}
+@vindex fortran-analyze-depth
+@vindex fortran-tab-mode-default
+ Fortran mode can use either style of continuation line. When you
+enter Fortran mode, it tries to deduce the proper continuation style
+automatically from the buffer contents. It does this by scanning up to
+@code{fortran-analyze-depth} (default 100) lines from the start of the
+buffer. The first line that begins with either a tab character or six
+spaces determines the choice. If the scan fails (for example, if the
+buffer is new and therefore empty), the value of
+@code{fortran-tab-mode-default} (@code{nil} for fixed format, and
+non-@code{nil} for tab format) is used. @samp{/t} in the mode line
+indicates tab format is selected. Fortran mode sets the value of
+@code{indent-tabs-mode} accordingly.
+
+ If the text on a line starts with the Fortran continuation marker
+@samp{$}, or if it begins with any non-whitespace character in column
+5, Fortran mode treats it as a continuation line. When you indent a
+continuation line with @key{TAB}, it converts the line to the current
+continuation style. When you split a Fortran statement with
+@kbd{C-M-j}, the continuation marker on the newline is created according
+to the continuation style.
+
+ The setting of continuation style affects several other aspects of
+editing in Fortran mode. In fixed format mode, the minimum column
+number for the body of a statement is 6. Lines inside of Fortran
+blocks that are indented to larger column numbers always use only the
+space character for whitespace. In tab format mode, the minimum
+column number for the statement body is 8, and the whitespace before
+column 8 must always consist of one tab character.
+
+@node ForIndent Num
+@subsubsection Line Numbers
+
+ If a number is the first non-whitespace in the line, Fortran
+indentation assumes it is a line number and moves it to columns 0
+through 4. (Columns always count from 0 in GNU Emacs.)
+
+@vindex fortran-line-number-indent
+ Line numbers of four digits or less are normally indented one space.
+The variable @code{fortran-line-number-indent} controls this; it
+specifies the maximum indentation a line number can have. The default
+value of the variable is 1. Fortran mode tries to prevent line number
+digits passing column 4, reducing the indentation below the specified
+maximum if necessary. If @code{fortran-line-number-indent} has the
+value 5, line numbers are right-justified to end in column 4.
+
+@vindex fortran-electric-line-number
+ Simply inserting a line number is enough to indent it according to
+these rules. As each digit is inserted, the indentation is recomputed.
+To turn off this feature, set the variable
+@code{fortran-electric-line-number} to @code{nil}.
+
+
+@node ForIndent Conv
+@subsubsection Syntactic Conventions
+
+ Fortran mode assumes that you follow certain conventions that simplify
+the task of understanding a Fortran program well enough to indent it
+properly:
+
+@itemize @bullet
+@item
+Two nested @samp{do} loops never share a @samp{continue} statement.
+
+@item
+Fortran keywords such as @samp{if}, @samp{else}, @samp{then}, @samp{do}
+and others are written without embedded whitespace or line breaks.
+
+Fortran compilers generally ignore whitespace outside of string
+constants, but Fortran mode does not recognize these keywords if they
+are not contiguous. Constructs such as @samp{else if} or @samp{end do}
+are acceptable, but the second word should be on the same line as the
+first and not on a continuation line.
+@end itemize
+
+@noindent
+If you fail to follow these conventions, the indentation commands may
+indent some lines unaesthetically. However, a correct Fortran program
+retains its meaning when reindented even if the conventions are not
+followed.
+
+@node ForIndent Vars
+@subsubsection Variables for Fortran Indentation
+
+@vindex fortran-do-indent
+@vindex fortran-if-indent
+@vindex fortran-structure-indent
+@vindex fortran-continuation-indent
+@vindex fortran-check-all-num@dots{}
+@vindex fortran-minimum-statement-indent@dots{}
+ Several additional variables control how Fortran indentation works:
+
+@table @code
+@item fortran-do-indent
+Extra indentation within each level of @samp{do} statement (default 3).
+
+@item fortran-if-indent
+Extra indentation within each level of @samp{if}, @samp{select case}, or
+@samp{where} statements (default 3).
+
+@item fortran-structure-indent
+Extra indentation within each level of @samp{structure}, @samp{union},
+@samp{map}, or @samp{interface} statements (default 3).
+
+@item fortran-continuation-indent
+Extra indentation for bodies of continuation lines (default 5).
+
+@item fortran-check-all-num-for-matching-do
+In Fortran77, a numbered @samp{do} statement is ended by any statement
+with a matching line number. It is common (but not compulsory) to use a
+@samp{continue} statement for this purpose. If this variable has a
+non-@code{nil} value, indenting any numbered statement must check for a
+@samp{do} that ends there. If you always end @samp{do} statements with
+a @samp{continue} line (or if you use the more modern @samp{enddo}),
+then you can speed up indentation by setting this variable to
+@code{nil}. The default is @code{nil}.
+
+@item fortran-blink-matching-if
+If this is @code{t}, indenting an @samp{endif} (or @samp{enddo}
+statement moves the cursor momentarily to the matching @samp{if} (or
+@samp{do}) statement to show where it is. The default is @code{nil}.
+
+@item fortran-minimum-statement-indent-fixed
+Minimum indentation for Fortran statements when using fixed format
+continuation line style. Statement bodies are never indented less than
+this much. The default is 6.
+
+@item fortran-minimum-statement-indent-tab
+Minimum indentation for Fortran statements for tab format continuation line
+style. Statement bodies are never indented less than this much. The
+default is 8.
+@end table
+
+The variables controlling the indentation of comments are described in
+the following section.
+
+@node Fortran Comments
+@subsection Fortran Comments
+
+ The usual Emacs comment commands assume that a comment can follow a
+line of code. In Fortran77, the standard comment syntax requires an
+entire line to be just a comment. Therefore, Fortran mode replaces the
+standard Emacs comment commands and defines some new variables.
+
+@vindex fortran-comment-line-start
+ Fortran mode can also handle the Fortran90 comment syntax where comments
+start with @samp{!} and can follow other text. Because only some Fortran77
+compilers accept this syntax, Fortran mode will not insert such comments
+unless you have said in advance to do so. To do this, set the variable
+@code{fortran-comment-line-start} to @samp{"!"}.
+
+@table @kbd
+@item M-;
+Align comment or insert new comment (@code{fortran-indent-comment}).
+
+@item C-x ;
+Applies to nonstandard @samp{!} comments only.
+
+@item C-c ;
+Turn all lines of the region into comments, or (with argument) turn them back
+into real code (@code{fortran-comment-region}).
+@end table
+
+@findex fortran-indent-comment
+ @kbd{M-;} in Fortran mode is redefined as the command
+@code{fortran-indent-comment}. Like the usual @kbd{M-;} command, this
+recognizes any kind of existing comment and aligns its text appropriately;
+if there is no existing comment, a comment is inserted and aligned. But
+inserting and aligning comments are not the same in Fortran mode as in
+other modes.
+
+ When a new comment must be inserted, if the current line is blank, a
+full-line comment is inserted. On a non-blank line, a nonstandard @samp{!}
+comment is inserted if you have said you want to use them. Otherwise a
+full-line comment is inserted on a new line before the current line.
+
+ Nonstandard @samp{!} comments are aligned like comments in other
+languages, but full-line comments are different. In a standard full-line
+comment, the comment delimiter itself must always appear in column zero.
+What can be aligned is the text within the comment. You can choose from
+three styles of alignment by setting the variable
+@code{fortran-comment-indent-style} to one of these values:
+
+@vindex fortran-comment-indent-style
+@vindex fortran-comment-line-extra-indent
+@table @code
+@item fixed
+Align the text at a fixed column, which is the sum of
+@code{fortran-comment-line-extra-indent} and the minimum statement
+indentation. This is the default.
+
+The minimum statement indentation is
+@code{fortran-minimum-statement-indent-fixed} for fixed format
+continuation line style and @code{fortran-minimum-statement-indent-tab}
+for tab format style.
+
+@item relative
+Align the text as if it were a line of code, but with an additional
+@code{fortran-comment-line-extra-indent} columns of indentation.
+
+@item nil
+Don't move text in full-line comments automatically.
+@end table
+
+@vindex fortran-comment-indent-char
+ In addition, you can specify the character to be used to indent within
+full-line comments by setting the variable
+@code{fortran-comment-indent-char} to the single-character string you want
+to use.
+
+@vindex fortran-directive-re
+ Compiler directive lines, or preprocessor lines, have much the same
+appearance as comment lines. It is important, though, that such lines
+never be indented at all, no matter what the value of
+@code{fortran-comment-indent-style}. The variable
+@code{fortran-directive-re} is a regular expression that specifies which
+lines are directives. Matching lines are never indented, and receive
+distinctive font-locking.
+
+ The normal Emacs comment command @kbd{C-x ;} has not been redefined. If
+you use @samp{!} comments, this command can be used with them. Otherwise
+it is useless in Fortran mode.
+
+@kindex C-c ; @r{(Fortran mode)}
+@findex fortran-comment-region
+@vindex fortran-comment-region
+ The command @kbd{C-c ;} (@code{fortran-comment-region}) turns all the
+lines of the region into comments by inserting the string @samp{C$$$} at
+the front of each one. With a numeric argument, it turns the region
+back into live code by deleting @samp{C$$$} from the front of each line
+in it. The string used for these comments can be controlled by setting
+the variable @code{fortran-comment-region}. Note that here we have an
+example of a command and a variable with the same name; these two uses
+of the name never conflict because in Lisp and in Emacs it is always
+clear from the context which one is meant.
+
+@node Fortran Autofill
+@subsection Auto Fill in Fortran Mode
+
+ Fortran mode has specialized support for Auto Fill mode, which is a
+minor mode that automatically splits statements as you insert them
+when they become too wide. Splitting a statement involves making
+continuation lines using @code{fortran-continuation-string}
+(@pxref{ForIndent Cont}). This splitting happens when you type
+@key{SPC}, @key{RET}, or @key{TAB}, and also in the Fortran
+indentation commands. You activate Auto Fill in Fortran mode in the
+normal way. @xref{Auto Fill,,, emacs, the Emacs Manual}.
+
+@vindex fortran-break-before-delimiters
+ Auto Fill breaks lines at spaces or delimiters when the lines get
+longer than the desired width (the value of @code{fill-column}). The
+delimiters (besides whitespace) that Auto Fill can break at are
+@samp{+}, @samp{-}, @samp{/}, @samp{*}, @samp{=}, @samp{<}, @samp{>},
+and @samp{,}. The line break comes after the delimiter if the
+variable @code{fortran-break-before-delimiters} is @code{nil}.
+Otherwise (and by default), the break comes before the delimiter.
+
+ To enable Auto Fill in all Fortran buffers, add
+@code{turn-on-auto-fill} to @code{fortran-mode-hook}. @xref{Hooks,,,
+emacs, the Emacs Manual}.
+
+@node Fortran Columns
+@subsection Checking Columns in Fortran
+
+@table @kbd
+@item C-c C-r
+Display a ``column ruler'' momentarily above the current line
+(@code{fortran-column-ruler}).
+@item C-c C-w
+Split the current window horizontally temporarily so that it is 72
+columns wide (@code{fortran-window-create-momentarily}). This may
+help you avoid making lines longer than the 72-character limit that
+some Fortran compilers impose.
+@item C-u C-c C-w
+Split the current window horizontally so that it is 72 columns wide
+(@code{fortran-window-create}). You can then continue editing.
+@item M-x fortran-strip-sequence-nos
+Delete all text in column 72 and beyond.
+@end table
+
+@kindex C-c C-r @r{(Fortran mode)}
+@findex fortran-column-ruler
+ The command @kbd{C-c C-r} (@code{fortran-column-ruler}) shows a column
+ruler momentarily above the current line. The comment ruler is two lines
+of text that show you the locations of columns with special significance in
+Fortran programs. Square brackets show the limits of the columns for line
+numbers, and curly brackets show the limits of the columns for the
+statement body. Column numbers appear above them.
+
+ Note that the column numbers count from zero, as always in GNU Emacs.
+As a result, the numbers may be one less than those you are familiar
+with; but the positions they indicate in the line are standard for
+Fortran.
+
+@vindex fortran-column-ruler-fixed
+@vindex fortran-column-ruler-tabs
+ The text used to display the column ruler depends on the value of the
+variable @code{indent-tabs-mode}. If @code{indent-tabs-mode} is
+@code{nil}, then the value of the variable
+@code{fortran-column-ruler-fixed} is used as the column ruler.
+Otherwise, the value of the variable @code{fortran-column-ruler-tab} is
+displayed. By changing these variables, you can change the column ruler
+display.
+
+@kindex C-c C-w @r{(Fortran mode)}
+@findex fortran-window-create-momentarily
+ @kbd{C-c C-w} (@code{fortran-window-create-momentarily}) temporarily
+splits the current window horizontally, making a window 72 columns
+wide, so you can see any lines that are too long. Type a space to
+restore the normal width.
+
+@kindex C-u C-c C-w @r{(Fortran mode)}
+@findex fortran-window-create
+ You can also split the window horizontally and continue editing with
+the split in place. To do this, use @kbd{C-u C-c C-w} (@code{M-x
+fortran-window-create}). By editing in this window you can
+immediately see when you make a line too wide to be correct Fortran.
+
+@findex fortran-strip-sequence-nos
+ The command @kbd{M-x fortran-strip-sequence-nos} deletes all text in
+column 72 and beyond, on all lines in the current buffer. This is the
+easiest way to get rid of old sequence numbers.
+
+@node Fortran Abbrev
+@subsection Fortran Keyword Abbrevs
+
+ Fortran mode provides many built-in abbrevs for common keywords and
+declarations. These are the same sort of abbrev that you can define
+yourself. To use them, you must turn on Abbrev mode.
+@xref{Abbrevs,,, emacs, the Emacs Manual}.
+
+ The built-in abbrevs are unusual in one way: they all start with a
+semicolon. You cannot normally use semicolon in an abbrev, but Fortran
+mode makes this possible by changing the syntax of semicolon to ``word
+constituent.''
+
+ For example, one built-in Fortran abbrev is @samp{;c} for
+@samp{continue}. If you insert @samp{;c} and then insert a punctuation
+character such as a space or a newline, the @samp{;c} expands automatically
+to @samp{continue}, provided Abbrev mode is enabled.@refill
+
+ Type @samp{;?} or @samp{;C-h} to display a list of all the built-in
+Fortran abbrevs and what they stand for.
--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node MS-DOS
+@section Emacs and MS-DOS
+@cindex MS-DOG
+@cindex MS-DOS peculiarities
+
+ This section briefly describes the peculiarities of using Emacs on
+the MS-DOS ``operating system'' (also known as ``MS-DOG'').
+Information about Emacs and Microsoft's current operating system
+Windows (also known as ``Losedows) is in the main Emacs manual
+(@pxref{Microsoft Systems,,, emacs, the Emacs Manual}).
+
+ If you build Emacs for MS-DOS, the binary will also run on Windows
+3.X, Windows NT, Windows 9X/ME, Windows 2000, or OS/2 as a DOS
+application; all of this chapter applies for all of those systems, if
+you use an Emacs that was built for MS-DOS.
+
+ @xref{Text and Binary,,,emacs, the Emacs Manual}, for information
+about Emacs' special handling of text files under MS-DOS (and
+Windows).
+
+@menu
+* Keyboard: MS-DOS Keyboard. Keyboard conventions on MS-DOS.
+* Mouse: MS-DOS Mouse. Mouse conventions on MS-DOS.
+* Display: MS-DOS Display. Fonts, frames and display size on MS-DOS.
+* Files: MS-DOS File Names. File name conventions on MS-DOS.
+* Printing: MS-DOS Printing. Printing specifics on MS-DOS.
+* I18N: MS-DOS and MULE. Support for internationalization on MS-DOS.
+* Processes: MS-DOS Processes. Running subprocesses on MS-DOS.
+@end menu
+
+@node MS-DOS Keyboard
+@subsection Keyboard Usage on MS-DOS
+
+@kindex DEL @r{(MS-DOS)}
+@kindex BS @r{(MS-DOS)}
+ The key that is called @key{DEL} in Emacs (because that's how it is
+designated on most workstations) is known as @key{BS} (backspace) on a
+PC. That is why the PC-specific terminal initialization remaps the
+@key{BS} key to act as @key{DEL}; the @key{DELETE} key is remapped to act
+as @kbd{C-d} for the same reasons.
+
+@kindex C-g @r{(MS-DOS)}
+@kindex C-BREAK @r{(MS-DOS)}
+@cindex quitting on MS-DOS
+ Emacs built for MS-DOS recognizes @kbd{C-@key{BREAK}} as a quit
+character, just like @kbd{C-g}. This is because Emacs cannot detect
+that you have typed @kbd{C-g} until it is ready for more input. As a
+consequence, you cannot use @kbd{C-g} to stop a running command
+(@pxref{Quitting,,,emacs, the Emacs Manual}). By contrast,
+@kbd{C-@key{BREAK}} @emph{is} detected as soon as you type it (as
+@kbd{C-g} is on other systems), so it can be used to stop a running
+command and for emergency escape (@pxref{Emergency Escape,,,emacs, the
+Emacs Manual}).
+
+@cindex Meta (under MS-DOS)
+@cindex Hyper (under MS-DOS)
+@cindex Super (under MS-DOS)
+@vindex dos-super-key
+@vindex dos-hyper-key
+ The PC keyboard maps use the left @key{ALT} key as the @key{META} key.
+You have two choices for emulating the @key{SUPER} and @key{HYPER} keys:
+choose either the right @key{CTRL} key or the right @key{ALT} key by
+setting the variables @code{dos-hyper-key} and @code{dos-super-key} to 1
+or 2 respectively. If neither @code{dos-super-key} nor
+@code{dos-hyper-key} is 1, then by default the right @key{ALT} key is
+also mapped to the @key{META} key. However, if the MS-DOS international
+keyboard support program @file{KEYB.COM} is installed, Emacs will
+@emph{not} map the right @key{ALT} to @key{META}, since it is used for
+accessing characters like @kbd{~} and @kbd{@@} on non-US keyboard
+layouts; in this case, you may only use the left @key{ALT} as @key{META}
+key.
+
+@kindex C-j @r{(MS-DOS)}
+@vindex dos-keypad-mode
+ The variable @code{dos-keypad-mode} is a flag variable that controls
+what key codes are returned by keys in the numeric keypad. You can also
+define the keypad @key{ENTER} key to act like @kbd{C-j}, by putting the
+following line into your @file{_emacs} file:
+
+@smallexample
+;; @r{Make the @key{ENTER} key from the numeric keypad act as @kbd{C-j}.}
+(define-key function-key-map [kp-enter] [?\C-j])
+@end smallexample
+
+@node MS-DOS Mouse
+@subsection Mouse Usage on MS-DOS
+
+@cindex mouse support under MS-DOS
+ Emacs on MS-DOS supports a mouse (on the default terminal only).
+The mouse commands work as documented, including those that use menus
+and the menu bar (@pxref{Menu Bar,,,emacs, the Emacs Manual}). Scroll
+bars don't work in MS-DOS Emacs. PC mice usually have only two
+buttons; these act as @kbd{Mouse-1} and @kbd{Mouse-2}, but if you
+press both of them together, that has the effect of @kbd{Mouse-3}. If
+the mouse does have 3 buttons, Emacs detects that at startup, and all
+the 3 buttons function normally, as on X.
+
+ Help strings for menu-bar and pop-up menus are displayed in the echo
+area when the mouse pointer moves across the menu items. Highlighting
+of mouse-sensitive text (@pxref{Mouse References,,,emacs, the Emacs
+Manual}) is also supported.
+
+@cindex mouse, set number of buttons
+@findex msdos-set-mouse-buttons
+ Some versions of mouse drivers don't report the number of mouse
+buttons correctly. For example, mice with a wheel report that they
+have 3 buttons, but only 2 of them are passed to Emacs; the clicks on
+the wheel, which serves as the middle button, are not passed. In
+these cases, you can use the @kbd{M-x msdos-set-mouse-buttons} command
+to tell Emacs how many mouse buttons to expect. You could make such a
+setting permanent by adding this fragment to your @file{_emacs} init
+file:
+
+@example
+;; @r{Treat the mouse like a 2-button mouse.}
+(msdos-set-mouse-buttons 2)
+@end example
+
+@cindex Windows clipboard support
+ Emacs built for MS-DOS supports clipboard operations when it runs on
+Windows. Commands that put text on the kill ring, or yank text from
+the ring, check the Windows clipboard first, just as Emacs does on the
+X Window System (@pxref{Mouse Commands,,,emacs, the Emacs Manual}).
+Only the primary selection and the cut buffer are supported by MS-DOS
+Emacs on Windows; the secondary selection always appears as empty.
+
+ Due to the way clipboard access is implemented by Windows, the
+length of text you can put into the clipboard is limited by the amount
+of free DOS memory that is available to Emacs. Usually, up to 620KB of
+text can be put into the clipboard, but this limit depends on the system
+configuration and is lower if you run Emacs as a subprocess of
+another program. If the killed text does not fit, Emacs outputs a
+message saying so, and does not put the text into the clipboard.
+
+ Null characters also cannot be put into the Windows clipboard. If the
+killed text includes null characters, Emacs does not put such text into
+the clipboard, and displays in the echo area a message to that effect.
+
+@vindex dos-display-scancodes
+ The variable @code{dos-display-scancodes}, when non-@code{nil},
+directs Emacs to display the @acronym{ASCII} value and the keyboard scan code of
+each keystroke; this feature serves as a complement to the
+@code{view-lossage} command, for debugging.
+
+@node MS-DOS Display
+@subsection Display on MS-DOS
+@cindex faces under MS-DOS
+@cindex fonts, emulating under MS-DOS
+
+ Display on MS-DOS cannot use font variants, like bold or italic, but
+it does support multiple faces, each of which can specify a foreground
+and a background color. Therefore, you can get the full functionality
+of Emacs packages that use fonts (such as @code{font-lock}, Enriched
+Text mode, and others) by defining the relevant faces to use different
+colors. Use the @code{list-colors-display} command (@pxref{Frame
+Parameters,,,emacs, the Emacs Manual}) and the
+@code{list-faces-display} command (@pxref{Faces,,,emacs, the Emacs
+Manual}) to see what colors and faces are available and what they look
+like.
+
+ @xref{MS-DOS and MULE}, later in this chapter, for information on
+how Emacs displays glyphs and characters that aren't supported by the
+native font built into the DOS display.
+
+@cindex cursor shape on MS-DOS
+ When Emacs starts, it changes the cursor shape to a solid box. This
+is for compatibility with other systems, where the box cursor is the
+default in Emacs. This default shape can be changed to a bar by
+specifying the @code{cursor-type} parameter in the variable
+@code{default-frame-alist} (@pxref{Creating Frames,,,emacs, the Emacs
+Manual}). The MS-DOS terminal doesn't support a vertical-bar cursor,
+so the bar cursor is horizontal, and the @code{@var{width}} parameter,
+if specified by the frame parameters, actually determines its height.
+For this reason, the @code{bar} and @code{hbar} cursor types produce
+the same effect on MS-DOS. As an extension, the bar cursor
+specification can include the starting scan line of the cursor as well
+as its width, like this:
+
+@example
+ '(cursor-type bar @var{width} . @var{start})
+@end example
+
+@noindent
+In addition, if the @var{width} parameter is negative, the cursor bar
+begins at the top of the character cell.
+
+@cindex frames on MS-DOS
+ The MS-DOS terminal can only display a single frame at a time. The
+Emacs frame facilities work on MS-DOS much as they do on text-only
+terminals (@pxref{Frames,,,emacs, the Emacs Manual}). When you run
+Emacs from a DOS window on MS-Windows, you can make the visible frame
+smaller than the full screen, but Emacs still cannot display more than
+a single frame at a time.
+
+@cindex frame size under MS-DOS
+@findex mode4350
+@findex mode25
+ The @code{mode4350} command switches the display to 43 or 50
+lines, depending on your hardware; the @code{mode25} command switches
+to the default 80x25 screen size.
+
+ By default, Emacs only knows how to set screen sizes of 80 columns by
+25, 28, 35, 40, 43 or 50 rows. However, if your video adapter has
+special video modes that will switch the display to other sizes, you can
+have Emacs support those too. When you ask Emacs to switch the frame to
+@var{n} rows by @var{m} columns dimensions, it checks if there is a
+variable called @code{screen-dimensions-@var{n}x@var{m}}, and if so,
+uses its value (which must be an integer) as the video mode to switch
+to. (Emacs switches to that video mode by calling the BIOS @code{Set
+Video Mode} function with the value of
+@code{screen-dimensions-@var{n}x@var{m}} in the @code{AL} register.)
+For example, suppose your adapter will switch to 66x80 dimensions when
+put into video mode 85. Then you can make Emacs support this screen
+size by putting the following into your @file{_emacs} file:
+
+@example
+(setq screen-dimensions-66x80 85)
+@end example
+
+ Since Emacs on MS-DOS can only set the frame size to specific
+supported dimensions, it cannot honor every possible frame resizing
+request. When an unsupported size is requested, Emacs chooses the next
+larger supported size beyond the specified size. For example, if you
+ask for 36x80 frame, you will get 40x80 instead.
+
+ The variables @code{screen-dimensions-@var{n}x@var{m}} are used only
+when they exactly match the specified size; the search for the next
+larger supported size ignores them. In the above example, even if your
+VGA supports 38x80 dimensions and you define a variable
+@code{screen-dimensions-38x80} with a suitable value, you will still get
+40x80 screen when you ask for a 36x80 frame. If you want to get the
+38x80 size in this case, you can do it by setting the variable named
+@code{screen-dimensions-36x80} with the same video mode value as
+@code{screen-dimensions-38x80}.
+
+ Changing frame dimensions on MS-DOS has the effect of changing all the
+other frames to the new dimensions.
+
+@node MS-DOS File Names
+@subsection File Names on MS-DOS
+@cindex file names under MS-DOS
+@cindex init file, default name under MS-DOS
+
+ On MS-DOS, file names are case-insensitive and limited to eight
+characters, plus optionally a period and three more characters. Emacs
+knows enough about these limitations to handle file names that were
+meant for other operating systems. For instance, leading dots
+@samp{.} in file names are invalid in MS-DOS, so Emacs transparently
+converts them to underscores @samp{_}; thus your default init file
+(@pxref{Init File,,,emacs, the Emacs Manual}) is called @file{_emacs}
+on MS-DOS. Excess characters before or after the period are generally
+ignored by MS-DOS itself; thus, if you visit the file
+@file{LongFileName.EvenLongerExtension}, you will silently get
+@file{longfile.eve}, but Emacs will still display the long file name
+on the mode line. Other than that, it's up to you to specify file
+names which are valid under MS-DOS; the transparent conversion as
+described above only works on file names built into Emacs.
+
+@cindex backup file names on MS-DOS
+ The above restrictions on the file names on MS-DOS make it almost
+impossible to construct the name of a backup file (@pxref{Backup
+Names,,,emacs, the Emacs Manual}) without losing some of the original
+file name characters. For example, the name of a backup file for
+@file{docs.txt} is @file{docs.tx~} even if single backup is used.
+
+@cindex file names under Windows 95/NT
+@cindex long file names in DOS box under Windows 95/NT
+ If you run Emacs as a DOS application under Windows 9X, Windows ME, or
+Windows 2000, you can turn on support for long file names. If you do
+that, Emacs doesn't truncate file names or convert them to lower case;
+instead, it uses the file names that you specify, verbatim. To enable
+long file name support, set the environment variable @env{LFN} to
+@samp{y} before starting Emacs. Unfortunately, Windows NT doesn't allow
+DOS programs to access long file names, so Emacs built for MS-DOS will
+only see their short 8+3 aliases.
+
+@cindex @env{HOME} directory under MS-DOS
+ MS-DOS has no notion of home directory, so Emacs on MS-DOS pretends
+that the directory where it is installed is the value of the @env{HOME}
+environment variable. That is, if your Emacs binary,
+@file{emacs.exe}, is in the directory @file{c:/utils/emacs/bin}, then
+Emacs acts as if @env{HOME} were set to @samp{c:/utils/emacs}. In
+particular, that is where Emacs looks for the init file @file{_emacs}.
+With this in mind, you can use @samp{~} in file names as an alias for
+the home directory, as you would on GNU or Unix. You can also set
+@env{HOME} variable in the environment before starting Emacs; its
+value will then override the above default behavior.
+
+ Emacs on MS-DOS handles the directory name @file{/dev} specially,
+because of a feature in the emulator libraries of DJGPP that pretends
+I/O devices have names in that directory. We recommend that you avoid
+using an actual directory named @file{/dev} on any disk.
+
+@node MS-DOS Printing
+@subsection Printing and MS-DOS
+
+ Printing commands, such as @code{lpr-buffer}
+(@pxref{Printing,,,emacs, the Emacs Manual}) and
+@code{ps-print-buffer} (@pxref{PostScript,,,emacs, the Emacs Manual})
+can work on MS-DOS by sending the output to one of the printer ports,
+if a Posix-style @code{lpr} program is unavailable. The same Emacs
+variables control printing on all systems, but in some cases they have
+different default values on MS-DOS.
+
+@xref{MS-Windows Printing,,,emacs, the Emacs Manual}, for details.
+
+ Some printers expect DOS codepage encoding of non-@acronym{ASCII} text, even
+though they are connected to a Windows machine which uses a different
+encoding for the same locale. For example, in the Latin-1 locale, DOS
+uses codepage 850 whereas Windows uses codepage 1252. @xref{MS-DOS and
+MULE}. When you print to such printers from Windows, you can use the
+@kbd{C-x RET c} (@code{universal-coding-system-argument}) command before
+@kbd{M-x lpr-buffer}; Emacs will then convert the text to the DOS
+codepage that you specify. For example, @kbd{C-x RET c cp850-dos RET
+M-x lpr-region RET} will print the region while converting it to the
+codepage 850 encoding. You may need to create the @code{cp@var{nnn}}
+coding system with @kbd{M-x codepage-setup}.
+
+@vindex dos-printer
+@vindex dos-ps-printer
+ For backwards compatibility, the value of @code{dos-printer}
+(@code{dos-ps-printer}), if it has a value, overrides the value of
+@code{printer-name} (@code{ps-printer-name}), on MS-DOS.
+
+
+@node MS-DOS and MULE
+@subsection International Support on MS-DOS
+@cindex international support @r{(MS-DOS)}
+
+ Emacs on MS-DOS supports the same international character sets as it
+does on GNU, Unix and other platforms (@pxref{International,,,emacs,
+the Emacs Manual}), including coding systems for converting between
+the different character sets. However, due to incompatibilities
+between MS-DOS/MS-Windows and other systems, there are several
+DOS-specific aspects of this support that you should be aware of.
+This section describes these aspects.
+
+ The description below is largely specific to the MS-DOS port of
+Emacs, especially where it talks about practical implications for
+Emacs users. For other operating systems, see the @file{code-pages.el}
+package, which implements support for MS-DOS- and MS-Windows-specific
+encodings for all platforms other than MS-DOS.
+
+@table @kbd
+@item M-x dos-codepage-setup
+Set up Emacs display and coding systems as appropriate for the current
+DOS codepage.
+
+@item M-x codepage-setup
+Create a coding system for a certain DOS codepage.
+@end table
+
+@cindex codepage, MS-DOS
+@cindex DOS codepages
+ MS-DOS is designed to support one character set of 256 characters at
+any given time, but gives you a variety of character sets to choose
+from. The alternative character sets are known as @dfn{DOS codepages}.
+Each codepage includes all 128 @acronym{ASCII} characters, but the other 128
+characters (codes 128 through 255) vary from one codepage to another.
+Each DOS codepage is identified by a 3-digit number, such as 850, 862,
+etc.
+
+ In contrast to X, which lets you use several fonts at the same time,
+MS-DOS normally doesn't allow use of several codepages in a single
+session. MS-DOS was designed to load a single codepage at system
+startup, and require you to reboot in order to change
+it@footnote{Normally, one particular codepage is burnt into the
+display memory, while other codepages can be installed by modifying
+system configuration files, such as @file{CONFIG.SYS}, and rebooting.
+While there is third-party software that allows changing the codepage
+without rebooting, we describe here how a stock MS-DOS system
+behaves.}. Much the same limitation applies when you run DOS
+executables on other systems such as MS-Windows.
+
+@cindex unibyte operation @r{(MS-DOS)}
+ If you invoke Emacs on MS-DOS with the @samp{--unibyte} option
+(@pxref{Initial Options,,,emacs, the Emacs Manual}), Emacs does not
+perform any conversion of non-@acronym{ASCII} characters. Instead, it
+reads and writes any non-@acronym{ASCII} characters verbatim, and
+sends their 8-bit codes to the display verbatim. Thus, unibyte Emacs
+on MS-DOS supports the current codepage, whatever it may be, but
+cannot even represent any other characters.
+
+@vindex dos-codepage
+ For multibyte operation on MS-DOS, Emacs needs to know which
+characters the chosen DOS codepage can display. So it queries the
+system shortly after startup to get the chosen codepage number, and
+stores the number in the variable @code{dos-codepage}. Some systems
+return the default value 437 for the current codepage, even though the
+actual codepage is different. (This typically happens when you use the
+codepage built into the display hardware.) You can specify a different
+codepage for Emacs to use by setting the variable @code{dos-codepage} in
+your init file.
+
+@cindex language environment, automatic selection on @r{MS-DOS}
+ Multibyte Emacs supports only certain DOS codepages: those which can
+display Far-Eastern scripts, like the Japanese codepage 932, and those
+that encode a single ISO 8859 character set.
+
+ The Far-Eastern codepages can directly display one of the MULE
+character sets for these countries, so Emacs simply sets up to use the
+appropriate terminal coding system that is supported by the codepage.
+The special features described in the rest of this section mostly
+pertain to codepages that encode ISO 8859 character sets.
+
+ For the codepages which correspond to one of the ISO character sets,
+Emacs knows the character set name based on the codepage number. Emacs
+automatically creates a coding system to support reading and writing
+files that use the current codepage, and uses this coding system by
+default. The name of this coding system is @code{cp@var{nnn}}, where
+@var{nnn} is the codepage number.@footnote{The standard Emacs coding
+systems for ISO 8859 are not quite right for the purpose, because
+typically the DOS codepage does not match the standard ISO character
+codes. For example, the letter @samp{@,{c}} (@samp{c} with cedilla) has
+code 231 in the standard Latin-1 character set, but the corresponding
+DOS codepage 850 uses code 135 for this glyph.}
+
+@cindex mode line @r{(MS-DOS)}
+ All the @code{cp@var{nnn}} coding systems use the letter @samp{D}
+(for ``DOS'') as their mode-line mnemonic. Since both the terminal
+coding system and the default coding system for file I/O are set to
+the proper @code{cp@var{nnn}} coding system at startup, it is normal
+for the mode line on MS-DOS to begin with @samp{-DD\-}. @xref{Mode
+Line,,,emacs, the Emacs Manual}. Far-Eastern DOS terminals do not use
+the @code{cp@var{nnn}} coding systems, and thus their initial mode
+line looks like the Emacs default.
+
+ Since the codepage number also indicates which script you are using,
+Emacs automatically runs @code{set-language-environment} to select the
+language environment for that script (@pxref{Language
+Environments,,,emacs, the Emacs Manual}).
+
+ If a buffer contains a character belonging to some other ISO 8859
+character set, not the one that the chosen DOS codepage supports, Emacs
+displays it using a sequence of @acronym{ASCII} characters. For example, if the
+current codepage doesn't have a glyph for the letter @samp{@`o} (small
+@samp{o} with a grave accent), it is displayed as @samp{@{`o@}}, where
+the braces serve as a visual indication that this is a single character.
+(This may look awkward for some non-Latin characters, such as those from
+Greek or Hebrew alphabets, but it is still readable by a person who
+knows the language.) Even though the character may occupy several
+columns on the screen, it is really still just a single character, and
+all Emacs commands treat it as one.
+
+@cindex IBM graphics characters (MS-DOS)
+@cindex box-drawing characters (MS-DOS)
+@cindex line-drawing characters (MS-DOS)
+ Not all characters in DOS codepages correspond to ISO 8859
+characters---some are used for other purposes, such as box-drawing
+characters and other graphics. Emacs maps these characters to two
+special character sets called @code{eight-bit-control} and
+@code{eight-bit-graphic}, and displays them as their IBM glyphs.
+However, you should be aware that other systems might display these
+characters differently, so you should avoid them in text that might be
+copied to a different operating system, or even to another DOS machine
+that uses a different codepage.
+
+@vindex dos-unsupported-character-glyph
+ Emacs supports many other characters sets aside from ISO 8859, but it
+cannot display them on MS-DOS. So if one of these multibyte characters
+appears in a buffer, Emacs on MS-DOS displays them as specified by the
+@code{dos-unsupported-character-glyph} variable; by default, this glyph
+is an empty triangle. Use the @kbd{C-u C-x =} command to display the
+actual code and character set of such characters. @xref{Position
+Info,,,emacs, the Emacs Manual}.
+
+@findex codepage-setup
+ By default, Emacs defines a coding system to support the current
+codepage. To define a coding system for some other codepage (e.g., to
+visit a file written on a DOS machine in another country), use the
+@kbd{M-x codepage-setup} command. It prompts for the 3-digit code of
+the codepage, with completion, then creates the coding system for the
+specified codepage. You can then use the new coding system to read and
+write files, but you must specify it explicitly for the file command
+when you want to use it (@pxref{Text Coding,,,emacs, the Emacs Manual}).
+
+ These coding systems are also useful for visiting a file encoded using
+a DOS codepage, using Emacs running on some other operating system.
+
+@cindex MS-Windows codepages
+ MS-Windows provides its own codepages, which are different from the
+DOS codepages for the same locale. For example, DOS codepage 850
+supports the same character set as Windows codepage 1252; DOS codepage
+855 supports the same character set as Windows codepage 1251, etc.
+The MS-Windows version of Emacs uses the current codepage for display
+when invoked with the @samp{-nw} option. Support for codepages in the
+Windows port of Emacs is part of the @file{code-pages.el} package.
+
+@node MS-DOS Processes
+@subsection Subprocesses on MS-DOS
+
+@cindex compilation under MS-DOS
+@cindex inferior processes under MS-DOS
+@findex compile @r{(MS-DOS)}
+@findex grep @r{(MS-DOS)}
+ Because MS-DOS is a single-process ``operating system,''
+asynchronous subprocesses are not available. In particular, Shell
+mode and its variants do not work. Most Emacs features that use
+asynchronous subprocesses also don't work on MS-DOS, including
+Shell mode and GUD. When in doubt, try and see; commands that
+don't work output an error message saying that asynchronous processes
+aren't supported.
+
+ Compilation under Emacs with @kbd{M-x compile}, searching files with
+@kbd{M-x grep} and displaying differences between files with @kbd{M-x
+diff} do work, by running the inferior processes synchronously. This
+means you cannot do any more editing until the inferior process
+finishes.
+
+ Spell checking also works, by means of special support for synchronous
+invocation of the @code{ispell} program. This is slower than the
+asynchronous invocation on other platforms
+
+ Instead of the Shell mode, which doesn't work on MS-DOS, you can use
+the @kbd{M-x eshell} command. This invokes the Eshell package that
+implements a Posix-like shell entirely in Emacs Lisp.
+
+ By contrast, Emacs compiled as a native Windows application
+@strong{does} support asynchronous subprocesses. @xref{Windows
+Processes,,,emacs, the Emacs Manual}.
+
+@cindex printing under MS-DOS
+ Printing commands, such as @code{lpr-buffer}
+(@pxref{Printing,,,emacs, the Emacs Manual}) and
+@code{ps-print-buffer} (@pxref{PostScript,,,emacs, the Emacs Manual}),
+work in MS-DOS by sending the output to one of the printer ports.
+@xref{MS-DOS Printing,,,emacs, the Emacs Manual}.
+
+ When you run a subprocess synchronously on MS-DOS, make sure the
+program terminates and does not try to read keyboard input. If the
+program does not terminate on its own, you will be unable to terminate
+it, because MS-DOS provides no general way to terminate a process.
+Pressing @kbd{C-c} or @kbd{C-@key{BREAK}} might sometimes help in these
+cases.
+
+ Accessing files on other machines is not supported on MS-DOS. Other
+network-oriented commands such as sending mail, Web browsing, remote
+login, etc., don't work either, unless network access is built into
+MS-DOS with some network redirector.
+
+@cindex directory listing on MS-DOS
+@vindex dired-listing-switches @r{(MS-DOS)}
+ Dired on MS-DOS uses the @code{ls-lisp} package where other
+platforms use the system @code{ls} command. Therefore, Dired on
+MS-DOS supports only some of the possible options you can mention in
+the @code{dired-listing-switches} variable. The options that work are
+@samp{-A}, @samp{-a}, @samp{-c}, @samp{-i}, @samp{-r}, @samp{-S},
+@samp{-s}, @samp{-t}, and @samp{-u}.
--- /dev/null
+@c This file is included either in emacs-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node Picture Mode
+@chapter Editing Pictures
+@cindex pictures
+@cindex making pictures out of text characters
+@findex edit-picture
+
+ To edit a picture made out of text characters (for example, a picture
+of the division of a register into fields, as a comment in a program),
+use the command @kbd{M-x edit-picture} to enter Picture mode.
+
+ In Picture mode, editing is based on the @dfn{quarter-plane} model of
+text, according to which the text characters lie studded on an area that
+stretches infinitely far to the right and downward. The concept of the end
+of a line does not exist in this model; the most you can say is where the
+last nonblank character on the line is found.
+
+ Of course, Emacs really always considers text as a sequence of
+characters, and lines really do have ends. But Picture mode replaces
+the most frequently-used commands with variants that simulate the
+quarter-plane model of text. They do this by inserting spaces or by
+converting tabs to spaces.
+
+ Most of the basic editing commands of Emacs are redefined by Picture mode
+to do essentially the same thing but in a quarter-plane way. In addition,
+Picture mode defines various keys starting with the @kbd{C-c} prefix to
+run special picture editing commands.
+
+ One of these keys, @kbd{C-c C-c}, is particularly important. Often a
+picture is part of a larger file that is usually edited in some other
+major mode. @kbd{M-x edit-picture} records the name of the previous
+major mode so you can use the @kbd{C-c C-c} command
+(@code{picture-mode-exit}) later to go back to that mode. @kbd{C-c C-c}
+also deletes spaces from the ends of lines, unless given a numeric
+argument.
+
+ The special commands of Picture mode all work in other modes (provided
+the @file{picture} library is loaded), but are not bound to keys except
+in Picture mode. The descriptions below talk of moving ``one column''
+and so on, but all the picture mode commands handle numeric arguments as
+their normal equivalents do.
+
+@vindex picture-mode-hook
+ Turning on Picture mode runs the hook @code{picture-mode-hook}.
+Additional extensions to Picture mode can be found in
+@file{artist.el}.
+
+@menu
+* Basic Picture:: Basic concepts and simple commands of Picture Mode.
+* Insert in Picture:: Controlling direction of cursor motion
+ after "self-inserting" characters.
+* Tabs in Picture:: Various features for tab stops and indentation.
+* Rectangles in Picture:: Clearing and superimposing rectangles.
+@end menu
+
+@node Basic Picture
+@section Basic Editing in Picture Mode
+
+@findex picture-forward-column
+@findex picture-backward-column
+@findex picture-move-down
+@findex picture-move-up
+@cindex editing in Picture mode
+
+ Most keys do the same thing in Picture mode that they usually do, but
+do it in a quarter-plane style. For example, @kbd{C-f} is rebound to
+run @code{picture-forward-column}, a command which moves point one
+column to the right, inserting a space if necessary so that the actual
+end of the line makes no difference. @kbd{C-b} is rebound to run
+@code{picture-backward-column}, which always moves point left one
+column, converting a tab to multiple spaces if necessary. @kbd{C-n} and
+@kbd{C-p} are rebound to run @code{picture-move-down} and
+@code{picture-move-up}, which can either insert spaces or convert tabs
+as necessary to make sure that point stays in exactly the same column.
+@kbd{C-e} runs @code{picture-end-of-line}, which moves to after the last
+nonblank character on the line. There is no need to change @kbd{C-a},
+as the choice of screen model does not affect beginnings of
+lines.
+
+@findex picture-newline
+ Insertion of text is adapted to the quarter-plane screen model
+through the use of Overwrite mode (@pxref{Minor Modes,,, emacs, the
+Emacs Manual}.) Self-inserting characters replace existing text,
+column by column, rather than pushing existing text to the right.
+@key{RET} runs @code{picture-newline}, which just moves to the
+beginning of the following line so that new text will replace that
+line.
+
+@findex picture-backward-clear-column
+@findex picture-clear-column
+@findex picture-clear-line
+ In Picture mode, the commands that normally delete or kill text,
+instead erase text (replacing it with spaces). @key{DEL}
+(@code{picture-backward-clear-column}) replaces the preceding
+character with a space rather than removing it; this moves point
+backwards. @kbd{C-d} (@code{picture-clear-column}) replaces the next
+character or characters with spaces, but does not move point. (If you
+want to clear characters to spaces and move forward over them, use
+@key{SPC}.) @kbd{C-k} (@code{picture-clear-line}) really kills the
+contents of lines, but does not delete the newlines from the buffer.
+
+@findex picture-open-line
+ To do actual insertion, you must use special commands. @kbd{C-o}
+(@code{picture-open-line}) creates a blank line after the current
+line; it never splits a line. @kbd{C-M-o} (@code{split-line}) makes
+sense in Picture mode, so it is not changed. @kbd{C-j}
+(@code{picture-duplicate-line}) inserts another line with the same
+contents below the current line.
+
+@kindex C-c C-d @r{(Picture mode)}
+ To do actual deletion in Picture mode, use @kbd{C-w}, @kbd{C-c C-d}
+(which is defined as @code{delete-char}, as @kbd{C-d} is in other
+modes), or one of the picture rectangle commands (@pxref{Rectangles in
+Picture}).
+
+@node Insert in Picture
+@section Controlling Motion after Insert
+
+@findex picture-movement-up
+@findex picture-movement-down
+@findex picture-movement-left
+@findex picture-movement-right
+@findex picture-movement-nw
+@findex picture-movement-ne
+@findex picture-movement-sw
+@findex picture-movement-se
+@kindex C-c < @r{(Picture mode)}
+@kindex C-c > @r{(Picture mode)}
+@kindex C-c ^ @r{(Picture mode)}
+@kindex C-c . @r{(Picture mode)}
+@kindex C-c ` @r{(Picture mode)}
+@kindex C-c ' @r{(Picture mode)}
+@kindex C-c / @r{(Picture mode)}
+@kindex C-c \ @r{(Picture mode)}
+ Since ``self-inserting'' characters in Picture mode overwrite and move
+point, there is no essential restriction on how point should be moved.
+Normally point moves right, but you can specify any of the eight
+orthogonal or diagonal directions for motion after a ``self-inserting''
+character. This is useful for drawing lines in the buffer.
+
+@table @kbd
+@item C-c <
+@itemx C-c @key{LEFT}
+Move left after insertion (@code{picture-movement-left}).
+@item C-c >
+@itemx C-c @key{RIGHT}
+Move right after insertion (@code{picture-movement-right}).
+@item C-c ^
+@itemx C-c @key{UP}
+Move up after insertion (@code{picture-movement-up}).
+@item C-c .
+@itemx C-c @key{DOWN}
+Move down after insertion (@code{picture-movement-down}).
+@item C-c `
+@itemx C-c @key{HOME}
+Move up and left (``northwest'') after insertion (@code{picture-movement-nw}).
+@item C-c '
+@itemx C-c @key{PAGEUP}
+Move up and right (``northeast'') after insertion
+(@code{picture-movement-ne}).
+@item C-c /
+@itemx C-c @key{END}
+Move down and left (``southwest'') after insertion
+@*(@code{picture-movement-sw}).
+@item C-c \
+@itemx C-c @key{PAGEDOWN}
+Move down and right (``southeast'') after insertion
+@*(@code{picture-movement-se}).
+@end table
+
+@kindex C-c C-f @r{(Picture mode)}
+@kindex C-c C-b @r{(Picture mode)}
+@findex picture-motion
+@findex picture-motion-reverse
+ Two motion commands move based on the current Picture insertion
+direction. The command @kbd{C-c C-f} (@code{picture-motion}) moves in the
+same direction as motion after ``insertion'' currently does, while @kbd{C-c
+C-b} (@code{picture-motion-reverse}) moves in the opposite direction.
+
+@node Tabs in Picture
+@section Picture Mode Tabs
+
+@kindex M-TAB @r{(Picture mode)}
+@findex picture-tab-search
+@vindex picture-tab-chars
+ Two kinds of tab-like action are provided in Picture mode. Use
+@kbd{M-@key{TAB}} (@code{picture-tab-search}) for context-based tabbing.
+With no argument, it moves to a point underneath the next
+``interesting'' character that follows whitespace in the previous
+nonblank line. ``Next'' here means ``appearing at a horizontal position
+greater than the one point starts out at.'' With an argument, as in
+@kbd{C-u M-@key{TAB}}, this command moves to the next such interesting
+character in the current line. @kbd{M-@key{TAB}} does not change the
+text; it only moves point. ``Interesting'' characters are defined by
+the variable @code{picture-tab-chars}, which should define a set of
+characters. The syntax for this variable is like the syntax used inside
+of @samp{[@dots{}]} in a regular expression---but without the @samp{[}
+and the @samp{]}. Its default value is @code{"!-~"}.
+
+@findex picture-tab
+ @key{TAB} itself runs @code{picture-tab}, which operates based on the
+current tab stop settings; it is the Picture mode equivalent of
+@code{tab-to-tab-stop}. Normally it just moves point, but with a numeric
+argument it clears the text that it moves over.
+
+@kindex C-c TAB @r{(Picture mode)}
+@findex picture-set-tab-stops
+ The context-based and tab-stop-based forms of tabbing are brought
+together by the command @kbd{C-c @key{TAB}} (@code{picture-set-tab-stops}).
+This command sets the tab stops to the positions which @kbd{M-@key{TAB}}
+would consider significant in the current line. The use of this command,
+together with @key{TAB}, can get the effect of context-based tabbing. But
+@kbd{M-@key{TAB}} is more convenient in the cases where it is sufficient.
+
+ It may be convenient to prevent use of actual tab characters in
+pictures. For example, this prevents @kbd{C-x @key{TAB}} from messing
+up the picture. You can do this by setting the variable
+@code{indent-tabs-mode} to @code{nil}.
+
+@node Rectangles in Picture
+@section Picture Mode Rectangle Commands
+@cindex rectangles and Picture mode
+@cindex Picture mode and rectangles
+
+ Picture mode defines commands for working on rectangular pieces of
+the text in ways that fit with the quarter-plane model. The standard
+rectangle commands may also be useful. @xref{Rectangles,,, emacs, the
+Emacs Manual}.
+
+@table @kbd
+@item C-c C-k
+Clear out the region-rectangle with spaces
+(@code{picture-clear-rectangle}). With argument, delete the text.
+@item C-c C-w @var{r}
+Similar, but save rectangle contents in register @var{r} first
+(@code{picture-clear-rectangle-to-register}).
+@item C-c C-y
+Copy last killed rectangle into the buffer by overwriting, with upper
+left corner at point (@code{picture-yank-rectangle}). With argument,
+insert instead.
+@item C-c C-x @var{r}
+Similar, but use the rectangle in register @var{r}
+(@code{picture-yank-rectangle-from-register}).
+@end table
+
+@kindex C-c C-k @r{(Picture mode)}
+@kindex C-c C-w @r{(Picture mode)}
+@findex picture-clear-rectangle
+@findex picture-clear-rectangle-to-register
+ The picture rectangle commands @kbd{C-c C-k}
+(@code{picture-clear-rectangle}) and @kbd{C-c C-w}
+(@code{picture-clear-rectangle-to-register}) differ from the standard
+rectangle commands in that they normally clear the rectangle instead of
+deleting it; this is analogous with the way @kbd{C-d} is changed in Picture
+mode.
+
+ However, deletion of rectangles can be useful in Picture mode, so
+these commands delete the rectangle if given a numeric argument.
+@kbd{C-c C-k} either with or without a numeric argument saves the
+rectangle for @kbd{C-c C-y}.
+
+@kindex C-c C-y @r{(Picture mode)}
+@kindex C-c C-x @r{(Picture mode)}
+@findex picture-yank-rectangle
+@findex picture-yank-rectangle-from-register
+ The Picture mode commands for yanking rectangles differ from the
+standard ones in that they overwrite instead of inserting. This is
+the same way that Picture mode insertion of other text differs from
+other modes. @kbd{C-c C-y} (@code{picture-yank-rectangle}) inserts
+(by overwriting) the rectangle that was most recently killed, while
+@kbd{C-c C-x} (@code{picture-yank-rectangle-from-register}) does
+likewise for the rectangle found in a specified register.
--- /dev/null
+@c This file is included in emacs-xtra.texi when producing the printed
+@c version.
+@iftex
+@node Advanced VC Usage
+@section Advanced VC Usage
+
+ Commonly used features of Emacs' version control (VC) support are
+described in the main Emacs manual (@pxref{Version Control,,,emacs,
+the Emacs Manual}). This chapter describes more advanced VC usage.
+
+@menu
+* VC Dired Mode:: Listing files managed by version control.
+* VC Dired Commands:: Commands to use in a VC Dired buffer.
+* Remote Repositories:: Efficient access to remote CVS servers.
+* Snapshots:: Sets of file versions treated as a unit.
+* Miscellaneous VC:: Various other commands and features of VC.
+* Customizing VC:: Variables that change VC's behavior.
+@end menu
+@end iftex
+
+@iftex
+@include vc1-xtra.texi
+@include vc2-xtra.texi
+@end iftex
--- /dev/null
+@c This file is included either in vc-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node VC Dired Mode
+@subsection Dired under VC
+
+@cindex PCL-CVS
+@pindex cvs
+@cindex CVS Dired Mode
+ The VC Dired Mode described here works with all the version control
+systems that VC supports. Another more powerful facility, designed
+specifically for CVS, is called PCL-CVS. @xref{Top, , About PCL-CVS,
+pcl-cvs, PCL-CVS --- The Emacs Front-End to CVS}.
+
+@kindex C-x v d
+@findex vc-directory
+ When you are working on a large program, it is often useful to find
+out which files have changed within an entire directory tree, or to view
+the status of all files under version control at once, and to perform
+version control operations on collections of files. You can use the
+command @kbd{C-x v d} (@code{vc-directory}) to make a directory listing
+that includes only files relevant for version control.
+
+@vindex vc-dired-terse-display
+ @kbd{C-x v d} creates a buffer which uses VC Dired Mode. This looks
+much like an ordinary Dired buffer (@pxref{Dired,,,emacs, the
+Emacs Manual}); however, normally it shows only the noteworthy files
+(those locked or not up-to-date). This is called @dfn{terse display}.
+If you set the variable @code{vc-dired-terse-display} to @code{nil},
+then VC Dired shows all relevant files---those managed under version
+control, plus all subdirectories (@dfn{full display}). The command
+@kbd{v t} in a VC Dired buffer toggles between terse display and full
+display (@pxref{VC Dired Commands}).
+
+@vindex vc-dired-recurse
+ By default, VC Dired produces a recursive listing of noteworthy or
+relevant files at or below the given directory. You can change this by
+setting the variable @code{vc-dired-recurse} to @code{nil}; then VC
+Dired shows only the files in the given directory.
+
+ The line for an individual file shows the version control state in the
+place of the hard link count, owner, group, and size of the file. If
+the file is unmodified, in sync with the master file, the version
+control state shown is blank. Otherwise it consists of text in
+parentheses. Under RCS and SCCS, the name of the user locking the file
+is shown; under CVS, an abbreviated version of the @samp{cvs status}
+output is used. Here is an example using RCS:
+
+@smallexample
+@group
+ /home/jim/project:
+
+ -rw-r--r-- (jim) Apr 2 23:39 file1
+ -r--r--r-- Apr 5 20:21 file2
+@end group
+@end smallexample
+
+@noindent
+The files @samp{file1} and @samp{file2} are under version control,
+@samp{file1} is locked by user jim, and @samp{file2} is unlocked.
+
+ Here is an example using CVS:
+
+@smallexample
+@group
+ /home/joe/develop:
+
+ -rw-r--r-- (modified) Aug 2 1997 file1.c
+ -rw-r--r-- Apr 4 20:09 file2.c
+ -rw-r--r-- (merge) Sep 13 1996 file3.c
+@end group
+@end smallexample
+
+ Here @samp{file1.c} is modified with respect to the repository, and
+@samp{file2.c} is not. @samp{file3.c} is modified, but other changes
+have also been checked in to the repository---you need to merge them
+with the work file before you can check it in.
+
+@vindex vc-stay-local
+@vindex vc-cvs-stay-local
+ In the above, if the repository were on a remote machine, VC would
+only contact it when the variable @code{vc-stay-local} (or
+@code{vc-cvs-stay-local}) is nil (@pxref{CVS Options}). This is
+because access to the repository may be slow, or you may be working
+offline and not have access to the repository at all. As a
+consequence, VC would not be able to tell you that @samp{file3.c} is
+in the ``merge'' state; you would learn that only when you try to
+check-in your modified copy of the file, or use a command such as
+@kbd{C-x v m}.
+
+ In practice, this is not a problem because CVS handles this case
+consistently whenever it arises. In VC, you'll simply get prompted to
+merge the remote changes into your work file first. The benefits of
+less network communication usually outweigh the disadvantage of not
+seeing remote changes immediately.
+
+@vindex vc-directory-exclusion-list
+ When VC Dired displays subdirectories (in the ``full'' display mode),
+it omits some that should never contain any files under version control.
+By default, this includes Version Control subdirectories such as
+@samp{RCS} and @samp{CVS}; you can customize this by setting the
+variable @code{vc-directory-exclusion-list}.
+
+ You can fine-tune VC Dired's format by typing @kbd{C-u C-x v d}---as in
+ordinary Dired, that allows you to specify additional switches for the
+@samp{ls} command.
+
+@node VC Dired Commands
+@subsection VC Dired Commands
+
+ All the usual Dired commands work normally in VC Dired mode, except
+for @kbd{v}, which is redefined as the version control prefix. You can
+invoke VC commands such as @code{vc-diff} and @code{vc-print-log} by
+typing @kbd{v =}, or @kbd{v l}, and so on. Most of these commands apply
+to the file name on the current line.
+
+ The command @kbd{v v} (@code{vc-next-action}) operates on all the
+marked files, so that you can lock or check in several files at once.
+If it operates on more than one file, it handles each file according to
+its current state; thus, it might lock one file, but check in another
+file. This could be confusing; it is up to you to avoid confusing
+behavior by marking a set of files that are in a similar state. If no
+files are marked, @kbd{v v} operates on the file in the current line.
+
+ If any files call for check-in, @kbd{v v} reads a single log entry,
+then uses it for all the files being checked in. This is convenient for
+registering or checking in several files at once, as part of the same
+change.
+
+@findex vc-dired-toggle-terse-mode
+@findex vc-dired-mark-locked
+ You can toggle between terse display (only locked files, or files not
+up-to-date) and full display at any time by typing @kbd{v t}
+(@code{vc-dired-toggle-terse-mode}). There is also a special command
+@kbd{* l} (@code{vc-dired-mark-locked}), which marks all files currently
+locked (or, with CVS, all files not up-to-date). Thus, typing @kbd{* l
+t k} is another way to delete from the buffer all files except those
+currently locked.
--- /dev/null
+@c This file is included either in vc-xtra.texi (when producing the
+@c printed version) or in the main Emacs manual (for the on-line version).
+@node Remote Repositories
+@subsection Remote Repositories
+@cindex remote repositories (CVS)
+
+ A common way of using CVS is to set up a central CVS repository on
+some Internet host, then have each developer check out a personal
+working copy of the files on his local machine. Committing changes to
+the repository, and picking up changes from other users into one's own
+working area, then works by direct interactions with the CVS server.
+
+ One difficulty is that access to the CVS server is often slow, and
+that developers might need to work off-line as well. VC is designed
+to reduce the amount of network interaction necessary.
+
+@menu
+* Version Backups:: Keeping local copies of repository versions.
+* Local Version Control:: Using another version system for local editing.
+@end menu
+
+@node Version Backups
+@subsubsection Version Backups
+@cindex version backups
+
+@cindex automatic version backups
+ When VC sees that the CVS repository for a file is on a remote
+machine, it automatically makes local backups of unmodified versions
+of the file---@dfn{automatic version backups}. This means that you
+can compare the file to the repository version (@kbd{C-x v =}), or
+revert to that version (@kbd{C-x v u}), without any network
+interactions.
+
+ The local copy of the unmodified file is called a @dfn{version
+backup} to indicate that it corresponds exactly to a version that is
+stored in the repository. Note that version backups are not the same
+as ordinary Emacs backup files (@pxref{Backup,,,emacs, the Emacs
+Manual}). But they follow a similar naming convention.
+
+ For a file that comes from a remote CVS repository, VC makes a
+version backup whenever you save the first changes to the file, and
+removes it after you have committed your modified version to the
+repository. You can disable the making of automatic version backups by
+setting @code{vc-cvs-stay-local} to @code{nil} (@pxref{CVS Options}).
+
+@cindex manual version backups
+ The name of the automatic version backup for version @var{version}
+of file @var{file} is @code{@var{file}.~@var{version}.~}. This is
+almost the same as the name used by @kbd{C-x v ~} (@pxref{Old
+Versions,,,emacs, the Emacs Manual}), the only difference being
+the additional dot (@samp{.}) after the version number. This
+similarity is intentional, because both kinds of files store the same
+kind of information. The file made by @kbd{C-x v ~} acts as a
+@dfn{manual version backup}.
+
+ All the VC commands that operate on old versions of a file can use
+both kinds of version backups. For instance, @kbd{C-x v ~} uses
+either an automatic or a manual version backup, if possible, to get
+the contents of the version you request. Likewise, @kbd{C-x v =} and
+@kbd{C-x v u} use either an automatic or a manual version backup, if
+one of them exists, to get the contents of a version to compare or
+revert to. If you changed a file outside of Emacs, so that no
+automatic version backup was created for the previous text, you can
+create a manual backup of that version using @kbd{C-x v ~}, and thus
+obtain the benefit of the local copy for Emacs commands.
+
+ The only difference in Emacs's handling of manual and automatic
+version backups, once they exist, is that Emacs deletes automatic
+version backups when you commit to the repository. By contrast,
+manual version backups remain until you delete them.
+
+@node Local Version Control
+@subsubsection Local Version Control
+@cindex local version control
+@cindex local back end (version control)
+
+When you make many changes to a file that comes from a remote
+repository, it can be convenient to have version control on your local
+machine as well. You can then record intermediate versions, revert to
+a previous state, etc., before you actually commit your changes to the
+remote server.
+
+VC lets you do this by putting a file under a second, local version
+control system, so that the file is effectively registered in two
+systems at the same time. For the description here, we will assume
+that the remote system is CVS, and you use RCS locally, although the
+mechanism works with any combination of version control systems
+(@dfn{back ends}).
+
+To make it work with other back ends, you must make sure that the
+``more local'' back end comes before the ``more remote'' back end in
+the setting of @code{vc-handled-backends} (@pxref{Customizing VC}). By
+default, this variable is set up so that you can use remote CVS and
+local RCS as described here.
+
+To start using local RCS for a file that comes from a remote CVS
+server, you must @emph{register the file in RCS}, by typing @kbd{C-u
+C-x v v rcs @key{RET}}. (In other words, use @code{vc-next-action} with a
+prefix argument, and specify RCS as the back end.)
+
+You can do this at any time; it does not matter whether you have
+already modified the file with respect to the version in the CVS
+repository. If possible, VC tries to make the RCS master start with
+the unmodified repository version, then checks in any local changes
+as a new version. This works if you have not made any changes yet, or
+if the unmodified repository version exists locally as a version
+backup (@pxref{Version Backups}). If the unmodified version is not
+available locally, the RCS master starts with the modified version;
+the only drawback to this is that you cannot compare your changes
+locally to what is stored in the repository.
+
+The version number of the RCS master is derived from the current CVS
+version, starting a branch from it. For example, if the current CVS
+version is 1.23, the local RCS branch will be 1.23.1. Version 1.23 in
+the RCS master will be identical to version 1.23 under CVS; your first
+changes are checked in as 1.23.1.1. (If the unmodified file is not
+available locally, VC will check in the modified file twice, both as
+1.23 and 1.23.1.1, to make the revision numbers consistent.)
+
+If you do not use locking under CVS (the default), locking is also
+disabled for RCS, so that editing under RCS works exactly as under
+CVS.
+
+When you are done with local editing, you can commit the final version
+back to the CVS repository by typing @kbd{C-u C-x v v cvs @key{RET}}.
+This initializes the log entry buffer (@pxref{Log Buffer,,,emacs, the
+Emacs Manual}) to contain all the log entries you have recorded in the
+RCS master; you can edit them as you wish, and then commit in CVS by
+typing @kbd{C-c C-c}. If the commit is successful, VC removes the RCS
+master, so that the file is once again registered under CVS only.
+(The RCS master is not actually deleted, just renamed by appending
+@samp{~} to the name, so that you can refer to it later if you wish.)
+
+While using local RCS, you can pick up recent changes from the CVS
+repository into your local file, or commit some of your changes back
+to CVS, without terminating local RCS version control. To do this,
+switch to the CVS back end temporarily, with the @kbd{C-x v b} command:
+
+@table @kbd
+@item C-x v b
+Switch to another back end that the current file is registered
+under (@code{vc-switch-backend}).
+
+@item C-u C-x v b @var{backend} @key{RET}
+Switch to @var{backend} for the current file.
+@end table
+
+@kindex C-x v b
+@findex vc-switch-backend
+@kbd{C-x v b} does not change the buffer contents, or any files; it
+only changes VC's perspective on how to handle the file. Any
+subsequent VC commands for that file will operate on the back end that
+is currently selected.
+
+If the current file is registered in more than one back end, typing
+@kbd{C-x v b} ``cycles'' through all of these back ends. With a
+prefix argument, it asks for the back end to use in the minibuffer.
+
+Thus, if you are using local RCS, and you want to pick up some recent
+changes in the file from remote CVS, first visit the file, then type
+@kbd{C-x v b} to switch to CVS, and finally use @kbd{C-x v m
+@key{RET}} to merge the news (@pxref{Merging,,,emacs, the Emacs
+Manual}). You can then switch back to RCS by typing @kbd{C-x v b}
+again, and continue to edit locally.
+
+But if you do this, the revision numbers in the RCS master no longer
+correspond to those of CVS. Technically, this is not a problem, but
+it can become difficult to keep track of what is in the CVS repository
+and what is not. So we suggest that you return from time to time to
+CVS-only operation, by committing your local changes back to the
+repository using @kbd{C-u C-x v v cvs @key{RET}}.
+
+@node Snapshots
+@subsection Snapshots
+@cindex snapshots and version control
+
+ A @dfn{snapshot} is a named set of file versions (one for each
+registered file) that you can treat as a unit. One important kind of
+snapshot is a @dfn{release}, a (theoretically) stable version of the
+system that is ready for distribution to users.
+
+@menu
+* Making Snapshots:: The snapshot facilities.
+* Snapshot Caveats:: Things to be careful of when using snapshots.
+@end menu
+
+@node Making Snapshots
+@subsubsection Making and Using Snapshots
+
+ There are two basic commands for snapshots; one makes a
+snapshot with a given name, the other retrieves a named snapshot.
+
+@table @code
+@kindex C-x v s
+@findex vc-create-snapshot
+@item C-x v s @var{name} @key{RET}
+Define the last saved versions of every registered file in or under the
+current directory as a snapshot named @var{name}
+(@code{vc-create-snapshot}).
+
+@kindex C-x v r
+@findex vc-retrieve-snapshot
+@item C-x v r @var{name} @key{RET}
+For all registered files at or below the current directory level, select
+whatever versions correspond to the snapshot @var{name}
+(@code{vc-retrieve-snapshot}).
+
+This command reports an error if any files are locked at or below the
+current directory, without changing anything; this is to avoid
+overwriting work in progress.
+@end table
+
+ A snapshot uses a very small amount of resources---just enough to record
+the list of file names and which version belongs to the snapshot. Thus,
+you need not hesitate to create snapshots whenever they are useful.
+
+ You can give a snapshot name as an argument to @kbd{C-x v =} or
+@kbd{C-x v ~} (@pxref{Old Versions,,,emacs, the Emacs Manual}).
+Thus, you can use it to compare a snapshot against the current files,
+or two snapshots against each other, or a snapshot against a named
+version.
+
+@node Snapshot Caveats
+@subsubsection Snapshot Caveats
+
+@cindex named configurations (RCS)
+ VC's snapshot facilities are modeled on RCS's named-configuration
+support. They use RCS's native facilities for this, so
+snapshots made using RCS through VC are visible even when you bypass VC.
+
+ With CVS, Meta-CVS, and Subversion, VC also uses the native
+mechanism provided by that back end to make snapshots and retrieve them
+(@dfn{tags} for CVS and Meta-CVS, @dfn{copies} for Subversion).
+
+@c worded verbosely to avoid overfull hbox.
+ For SCCS, VC implements snapshots itself. The files it uses contain
+name/file/version-number triples. These snapshots are visible only
+through VC.
+
+ There is no support for VC snapshots using GNU Arch yet.
+
+ A snapshot is a set of checked-in versions. So make sure that all the
+files are checked in and not locked when you make a snapshot.
+
+ File renaming and deletion can create some difficulties with snapshots.
+This is not a VC-specific problem, but a general design issue in version
+control systems that no one has solved very well yet.
+
+ If you rename a registered file, you need to rename its master along
+with it (the command @code{vc-rename-file} does this automatically). If
+you are using SCCS, you must also update the records of the snapshot, to
+mention the file by its new name (@code{vc-rename-file} does this,
+too). An old snapshot that refers to a master file that no longer
+exists under the recorded name is invalid; VC can no longer retrieve
+it. It would be beyond the scope of this manual to explain enough about
+RCS and SCCS to explain how to update the snapshots by hand.
+
+ Using @code{vc-rename-file} makes the snapshot remain valid for
+retrieval, but it does not solve all problems. For example, some of the
+files in your program probably refer to others by name. At the very
+least, the makefile probably mentions the file that you renamed. If you
+retrieve an old snapshot, the renamed file is retrieved under its new
+name, which is not the name that the makefile expects. So the program
+won't really work as retrieved.
+
+@node Miscellaneous VC
+@subsection Miscellaneous Commands and Features of VC
+
+ This section explains the less-frequently-used features of VC.
+
+@menu
+* Change Logs and VC:: Generating a change log file from log entries.
+* Renaming and VC:: A command to rename both the source and master
+ file correctly.
+* Version Headers:: Inserting version control headers into working files.
+@end menu
+
+@node Change Logs and VC
+@subsubsection Change Logs and VC
+
+ If you use RCS or CVS for a program and also maintain a change log
+file for it (@pxref{Change Log,,,emacs, the Emacs Manual}), you
+can generate change log entries automatically from the version control
+log entries:
+
+@table @kbd
+@item C-x v a
+@kindex C-x v a
+@findex vc-update-change-log
+Visit the current directory's change log file and, for registered files
+in that directory, create new entries for versions checked in since the
+most recent entry in the change log file.
+(@code{vc-update-change-log}).
+
+This command works with RCS or CVS only, not with any of the other
+back ends.
+
+@item C-u C-x v a
+As above, but only find entries for the current buffer's file.
+
+@item M-1 C-x v a
+As above, but find entries for all the currently visited files that are
+maintained with version control. This works only with RCS, and it puts
+all entries in the log for the default directory, which may not be
+appropriate.
+@end table
+
+ For example, suppose the first line of @file{ChangeLog} is dated
+1999-04-10, and that the only check-in since then was by Nathaniel
+Bowditch to @file{rcs2log} on 1999-05-22 with log text @samp{Ignore log
+messages that start with `#'.}. Then @kbd{C-x v a} visits
+@file{ChangeLog} and inserts text like this:
+
+@iftex
+@medbreak
+@end iftex
+@smallexample
+@group
+1999-05-22 Nathaniel Bowditch <nat@@apn.org>
+
+ * rcs2log: Ignore log messages that start with `#'.
+@end group
+@end smallexample
+@iftex
+@medbreak
+@end iftex
+
+@noindent
+You can then edit the new change log entry further as you wish.
+
+ Some of the new change log entries may duplicate what's already in
+ChangeLog. You will have to remove these duplicates by hand.
+
+ Normally, the log entry for file @file{foo} is displayed as @samp{*
+foo: @var{text of log entry}}. The @samp{:} after @file{foo} is omitted
+if the text of the log entry starts with @w{@samp{(@var{functionname}):
+}}. For example, if the log entry for @file{vc.el} is
+@samp{(vc-do-command): Check call-process status.}, then the text in
+@file{ChangeLog} looks like this:
+
+@iftex
+@medbreak
+@end iftex
+@smallexample
+@group
+1999-05-06 Nathaniel Bowditch <nat@@apn.org>
+
+ * vc.el (vc-do-command): Check call-process status.
+@end group
+@end smallexample
+@iftex
+@medbreak
+@end iftex
+
+ When @kbd{C-x v a} adds several change log entries at once, it groups
+related log entries together if they all are checked in by the same
+author at nearly the same time. If the log entries for several such
+files all have the same text, it coalesces them into a single entry.
+For example, suppose the most recent check-ins have the following log
+entries:
+
+@flushleft
+@bullet{} For @file{vc.texinfo}: @samp{Fix expansion typos.}
+@bullet{} For @file{vc.el}: @samp{Don't call expand-file-name.}
+@bullet{} For @file{vc-hooks.el}: @samp{Don't call expand-file-name.}
+@end flushleft
+
+@noindent
+They appear like this in @file{ChangeLog}:
+
+@iftex
+@medbreak
+@end iftex
+@smallexample
+@group
+1999-04-01 Nathaniel Bowditch <nat@@apn.org>
+
+ * vc.texinfo: Fix expansion typos.
+
+ * vc.el, vc-hooks.el: Don't call expand-file-name.
+@end group
+@end smallexample
+@iftex
+@medbreak
+@end iftex
+
+ Normally, @kbd{C-x v a} separates log entries by a blank line, but you
+can mark several related log entries to be clumped together (without an
+intervening blank line) by starting the text of each related log entry
+with a label of the form @w{@samp{@{@var{clumpname}@} }}. The label
+itself is not copied to @file{ChangeLog}. For example, suppose the log
+entries are:
+
+@flushleft
+@bullet{} For @file{vc.texinfo}: @samp{@{expand@} Fix expansion typos.}
+@bullet{} For @file{vc.el}: @samp{@{expand@} Don't call expand-file-name.}
+@bullet{} For @file{vc-hooks.el}: @samp{@{expand@} Don't call expand-file-name.}
+@end flushleft
+
+@noindent
+Then the text in @file{ChangeLog} looks like this:
+
+@iftex
+@medbreak
+@end iftex
+@smallexample
+@group
+1999-04-01 Nathaniel Bowditch <nat@@apn.org>
+
+ * vc.texinfo: Fix expansion typos.
+ * vc.el, vc-hooks.el: Don't call expand-file-name.
+@end group
+@end smallexample
+@iftex
+@medbreak
+@end iftex
+
+ A log entry whose text begins with @samp{#} is not copied to
+@file{ChangeLog}. For example, if you merely fix some misspellings in
+comments, you can log the change with an entry beginning with @samp{#}
+to avoid putting such trivia into @file{ChangeLog}.
+
+@node Renaming and VC
+@subsubsection Renaming VC Work Files and Master Files
+
+@findex vc-rename-file
+ When you rename a registered file, you must also rename its master
+file correspondingly to get proper results. Use @code{vc-rename-file}
+to rename the source file as you specify, and rename its master file
+accordingly. It also updates any snapshots (@pxref{Snapshots}) that
+mention the file, so that they use the new name; despite this, the
+snapshot thus modified may not completely work (@pxref{Snapshot
+Caveats}).
+
+ Some back ends do not provide an explicit rename operation to their
+repositories. After issuing @code{vc-rename-file}, use @kbd{C-x v v}
+on the original and renamed buffers and provide the necessary edit
+log.
+
+ You cannot use @code{vc-rename-file} on a file that is locked by
+someone else.
+
+@node Version Headers
+@subsubsection Inserting Version Control Headers
+
+ Sometimes it is convenient to put version identification strings
+directly into working files. Certain special strings called
+@dfn{version headers} are replaced in each successive version by the
+number of that version, the name of the user who created it, and other
+relevant information. All of the back ends that VC supports have such
+a mechanism, except GNU Arch.
+
+ VC does not normally use the information contained in these headers.
+The exception is RCS---with RCS, version headers are sometimes more
+reliable than the master file to determine which version of the file
+you are editing. Note that in a multi-branch environment, version
+headers are necessary to make VC behave correctly (@pxref{Multi-User
+Branching,,,emacs, the Emacs Manual}).
+
+ Searching for RCS version headers is controlled by the variable
+@code{vc-consult-headers}. If it is non-@code{nil} (the default),
+Emacs searches for headers to determine the version number you are
+editing. Setting it to @code{nil} disables this feature.
+
+ Note that although CVS uses the same kind of version headers as RCS
+does, VC never searches for these headers if you are using CVS,
+regardless of the above setting.
+
+@kindex C-x v h
+@findex vc-insert-headers
+ You can use the @kbd{C-x v h} command (@code{vc-insert-headers}) to
+insert a suitable header string.
+
+@table @kbd
+@item C-x v h
+Insert headers in a file for use with your version-control system.
+@end table
+
+@vindex vc-@var{backend}-header
+ The default header string is @samp{@w{$}Id$} for RCS and
+@samp{@w{%}W%} for SCCS. You can specify other headers to insert by
+setting the variables @code{vc-@var{backend}-header} where
+@var{backend} is @code{rcs} or @code{sccs}.
+
+ Instead of a single string, you can specify a list of strings; then
+each string in the list is inserted as a separate header on a line of
+its own.
+
+ It may be necessary to use apparently-superfluous backslashes when
+writing the strings that you put in this variable. For instance, you
+might write @code{"$Id\$"} rather than @code{"$Id@w{$}"}. The extra
+backslash prevents the string constant from being interpreted as a
+header, if the Emacs Lisp file containing it is maintained with
+version control.
+
+@vindex vc-comment-alist
+ Each header is inserted surrounded by tabs, inside comment delimiters,
+on a new line at point. Normally the ordinary comment
+start and comment end strings of the current mode are used, but for
+certain modes, there are special comment delimiters for this purpose;
+the variable @code{vc-comment-alist} specifies them. Each element of
+this list has the form @code{(@var{mode} @var{starter} @var{ender})}.
+
+@vindex vc-static-header-alist
+ The variable @code{vc-static-header-alist} specifies further strings
+to add based on the name of the buffer. Its value should be a list of
+elements of the form @code{(@var{regexp} . @var{format})}. Whenever
+@var{regexp} matches the buffer name, @var{format} is inserted as part
+of the header. A header line is inserted for each element that matches
+the buffer name, and for each string specified by
+@code{vc-@var{backend}-header}. The header line is made by processing the
+string from @code{vc-@var{backend}-header} with the format taken from the
+element. The default value for @code{vc-static-header-alist} is as follows:
+
+@example
+@group
+(("\\.c$" .
+ "\n#ifndef lint\nstatic char vcid[] = \"\%s\";\n\
+#endif /* lint */\n"))
+@end group
+@end example
+
+@noindent
+It specifies insertion of text of this form:
+
+@example
+@group
+
+#ifndef lint
+static char vcid[] = "@var{string}";
+#endif /* lint */
+@end group
+@end example
+
+@noindent
+Note that the text above starts with a blank line.
+
+ If you use more than one version header in a file, put them close
+together in the file. The mechanism in @code{revert-buffer} that
+preserves markers may not handle markers positioned between two version
+headers.
+
+@node Customizing VC
+@subsection Customizing VC
+
+@vindex vc-handled-backends
+The variable @code{vc-handled-backends} determines which version
+control systems VC should handle. The default value is @code{(RCS CVS
+SVN SCCS Arch MCVS)}, so it contains all six version systems that are
+currently supported. If you want VC to ignore one or more of these
+systems, exclude its name from the list. To disable VC entirely, set
+this variable to @code{nil}.
+
+The order of systems in the list is significant: when you visit a file
+registered in more than one system (@pxref{Local Version Control}), VC
+uses the system that comes first in @code{vc-handled-backends} by
+default. The order is also significant when you register a file for
+the first time, @pxref{Registering,,,emacs, the Emacs Manual} for
+details.
+
+@menu
+* General VC Options:: Options that apply to multiple back ends.
+* RCS and SCCS:: Options for RCS and SCCS.
+* CVS Options:: Options for CVS.
+@end menu
+
+@node General VC Options
+@subsubsection General Options
+
+@vindex vc-make-backup-files
+ Emacs normally does not save backup files for source files that are
+maintained with version control. If you want to make backup files even
+for files that use version control, set the variable
+@code{vc-make-backup-files} to a non-@code{nil} value.
+
+@vindex vc-keep-workfiles
+ Normally the work file exists all the time, whether it is locked or
+not. If you set @code{vc-keep-workfiles} to @code{nil}, then checking
+in a new version with @kbd{C-x v v} deletes the work file; but any
+attempt to visit the file with Emacs creates it again. (With CVS, work
+files are always kept.)
+
+@vindex vc-follow-symlinks
+ Editing a version-controlled file through a symbolic link can be
+dangerous. It bypasses the version control system---you can edit the
+file without locking it, and fail to check your changes in. Also,
+your changes might overwrite those of another user. To protect against
+this, VC checks each symbolic link that you visit, to see if it points
+to a file under version control.
+
+ The variable @code{vc-follow-symlinks} controls what to do when a
+symbolic link points to a version-controlled file. If it is @code{nil},
+VC only displays a warning message. If it is @code{t}, VC automatically
+follows the link, and visits the real file instead, telling you about
+this in the echo area. If the value is @code{ask} (the default), VC
+asks you each time whether to follow the link.
+
+@vindex vc-suppress-confirm
+ If @code{vc-suppress-confirm} is non-@code{nil}, then @kbd{C-x v v}
+and @kbd{C-x v i} can save the current buffer without asking, and
+@kbd{C-x v u} also operates without asking for confirmation. (This
+variable does not affect @kbd{C-x v c}; that operation is so drastic
+that it should always ask for confirmation.)
+
+@vindex vc-command-messages
+ VC mode does much of its work by running the shell commands for RCS,
+CVS and SCCS. If @code{vc-command-messages} is non-@code{nil}, VC
+displays messages to indicate which shell commands it runs, and
+additional messages when the commands finish.
+
+@vindex vc-path
+ You can specify additional directories to search for version control
+programs by setting the variable @code{vc-path}. These directories
+are searched before the usual search path. It is rarely necessary to
+set this variable, because VC normally finds the proper files
+automatically.
+
+@node RCS and SCCS
+@subsubsection Options for RCS and SCCS
+
+@cindex non-strict locking (RCS)
+@cindex locking, non-strict (RCS)
+ By default, RCS uses locking to coordinate the activities of several
+users, but there is a mode called @dfn{non-strict locking} in which
+you can check-in changes without locking the file first. Use
+@samp{rcs -U} to switch to non-strict locking for a particular file,
+see the @code{rcs} manual page for details.
+
+ When deducing the version control state of an RCS file, VC first
+looks for an RCS version header string in the file (@pxref{Version
+Headers}). If there is no header string, VC normally looks at the
+file permissions of the work file; this is fast. But there might be
+situations when the file permissions cannot be trusted. In this case
+the master file has to be consulted, which is rather expensive. Also
+the master file can only tell you @emph{if} there's any lock on the
+file, but not whether your work file really contains that locked
+version.
+
+@vindex vc-consult-headers
+ You can tell VC not to use version headers to determine the file
+status by setting @code{vc-consult-headers} to @code{nil}. VC then
+always uses the file permissions (if it is supposed to trust them), or
+else checks the master file.
+
+@vindex vc-mistrust-permissions
+ You can specify the criterion for whether to trust the file
+permissions by setting the variable @code{vc-mistrust-permissions}.
+Its value can be @code{t} (always mistrust the file permissions and
+check the master file), @code{nil} (always trust the file
+permissions), or a function of one argument which makes the decision.
+The argument is the directory name of the @file{RCS} subdirectory. A
+non-@code{nil} value from the function says to mistrust the file
+permissions. If you find that the file permissions of work files are
+changed erroneously, set @code{vc-mistrust-permissions} to @code{t}.
+Then VC always checks the master file to determine the file's status.
+
+ VC determines the version control state of files under SCCS much as
+with RCS. It does not consider SCCS version headers, though. Thus,
+the variable @code{vc-mistrust-permissions} affects SCCS use, but
+@code{vc-consult-headers} does not.
+
+@node CVS Options
+@subsubsection Options specific for CVS
+
+@cindex locking (CVS)
+ By default, CVS does not use locking to coordinate the activities of
+several users; anyone can change a work file at any time. However,
+there are ways to restrict this, resulting in behavior that resembles
+locking.
+
+@cindex CVSREAD environment variable (CVS)
+ For one thing, you can set the @env{CVSREAD} environment variable
+(the value you use makes no difference). If this variable is defined,
+CVS makes your work files read-only by default. In Emacs, you must
+type @kbd{C-x v v} to make the file writable, so that editing works
+in fact similar as if locking was used. Note however, that no actual
+locking is performed, so several users can make their files writable
+at the same time. When setting @env{CVSREAD} for the first time, make
+sure to check out all your modules anew, so that the file protections
+are set correctly.
+
+@cindex cvs watch feature
+@cindex watching files (CVS)
+ Another way to achieve something similar to locking is to use the
+@dfn{watch} feature of CVS. If a file is being watched, CVS makes it
+read-only by default, and you must also use @kbd{C-x v v} in Emacs to
+make it writable. VC calls @code{cvs edit} to make the file writable,
+and CVS takes care to notify other developers of the fact that you
+intend to change the file. See the CVS documentation for details on
+using the watch feature.
+
+@vindex vc-stay-local
+@vindex vc-cvs-stay-local
+@cindex remote repositories (CVS)
+ When a file's repository is on a remote machine, VC tries to keep
+network interactions to a minimum. This is controlled by the variable
+@code{vc-cvs-stay-local}. There is another variable,
+@code{vc-stay-local}, which enables the feature also for other back
+ends that support it, including CVS. In the following, we will talk
+only about @code{vc-cvs-stay-local}, but everything applies to
+@code{vc-stay-local} as well.
+
+If @code{vc-cvs-stay-local} is @code{t} (the default), then VC uses
+only the entry in the local CVS subdirectory to determine the file's
+state (and possibly information returned by previous CVS commands).
+One consequence of this is that when you have modified a file, and
+somebody else has already checked in other changes to the file, you
+are not notified of it until you actually try to commit. (But you can
+try to pick up any recent changes from the repository first, using
+@kbd{C-x v m @key{RET}}, @pxref{Merging,,,emacs, the Emacs Manual}).
+
+ When @code{vc-cvs-stay-local} is @code{t}, VC also makes local
+version backups, so that simple diff and revert operations are
+completely local (@pxref{Version Backups}).
+
+ On the other hand, if you set @code{vc-cvs-stay-local} to @code{nil},
+then VC queries the remote repository @emph{before} it decides what to
+do in @code{vc-next-action} (@kbd{C-x v v}), just as it does for local
+repositories. It also does not make any version backups.
+
+ You can also set @code{vc-cvs-stay-local} to a regular expression
+that is matched against the repository host name; VC then stays local
+only for repositories from hosts that match the pattern.
+
+@vindex vc-cvs-global-switches
+ You can specify additional command line options to pass to all CVS
+operations in the variable @code{vc-cvs-global-switches}. These
+switches are inserted immediately after the @code{cvs} command, before
+the name of the operation to invoke.
projects / emacs.git / commitdiff