+File: xemacs.info, Node: Adding to Diary, Next: Special Diary Entries, Prev: Date Formats, Up: Diary
+
+Commands to Add to the Diary
+----------------------------
+
+ While in the calendar, there are several commands to create diary
+entries:
+
+`i d'
+ Add a diary entry for the selected date (`insert-diary-entry').
+
+`i w'
+ Add a diary entry for the selected day of the week
+ (`insert-weekly-diary-entry').
+
+`i m'
+ Add a diary entry for the selected day of the month
+ (`insert-monthly-diary-entry').
+
+`i y'
+ Add a diary entry for the selected day of the year
+ (`insert-yearly-diary-entry').
+
+ You can make a diary entry for a specific date by selecting that date
+in the calendar window and typing the `i d' command. This command
+displays the end of your diary file in another window and inserts the
+date; you can then type the rest of the diary entry.
+
+ If you want to make a diary entry that applies to a specific day of
+the week, select that day of the week (any occurrence will do) and type
+`i w'. This inserts the day-of-week as a generic date; you can then
+type the rest of the diary entry. You can make a monthly diary entry in
+the same fashion. Select the day of the month, use the `i m' command,
+and type rest of the entry. Similarly, you can insert a yearly diary
+entry with the `i y' command.
+
+ All of the above commands make marking diary entries by default. To
+make a nonmarking diary entry, give a numeric argument to the command.
+For example, `C-u i w' makes a nonmarking weekly diary entry.
+
+ When you modify the diary file, be sure to save the file before
+exiting Emacs.
+
+\1f
+File: xemacs.info, Node: Special Diary Entries, Prev: Adding to Diary, Up: Diary
+
+Special Diary Entries
+---------------------
+
+ In addition to entries based on calendar dates, the diary file can
+contain "sexp entries" for regular events such as anniversaries. These
+entries are based on Lisp expressions (sexps) that Emacs evaluates as
+it scans the diary file. Instead of a date, a sexp entry contains `%%'
+followed by a Lisp expression which must begin and end with
+parentheses. The Lisp expression determines which dates the entry
+applies to.
+
+ Calendar mode provides commands to insert certain commonly used sexp
+entries:
+
+`i a'
+ Add an anniversary diary entry for the selected date
+ (`insert-anniversary-diary-entry').
+
+`i b'
+ Add a block diary entry for the current region
+ (`insert-block-diary-entry').
+
+`i c'
+ Add a cyclic diary entry starting at the date
+ (`insert-cyclic-diary-entry').
+
+ If you want to make a diary entry that applies to the anniversary of
+a specific date, move point to that date and use the `i a' command.
+This displays the end of your diary file in another window and inserts
+the anniversary description; you can then type the rest of the diary
+entry. The entry looks like this:
+
+ The effect of `i a' is to add a `diary-anniversary' sexp to your
+diary file. You can also add one manually, for instance:
+
+ %%(diary-anniversary 10 31 1948) Arthur's birthday
+
+This entry applies to October 31 in any year after 1948; `10 31 1948'
+specifies the date. (If you are using the European calendar style, the
+month and day are interchanged.) The reason this expression requires a
+beginning year is that advanced diary functions can use it to calculate
+the number of elapsed years.
+
+ A "block" diary entry applies to a specified range of consecutive
+dates. Here is a block diary entry that applies to all dates from June
+24, 1990 through July 10, 1990:
+
+ %%(diary-block 6 24 1990 7 10 1990) Vacation
+
+The `6 24 1990' indicates the starting date and the `7 10 1990'
+indicates the stopping date. (Again, if you are using the European
+calendar style, the month and day are interchanged.)
+
+ To insert a block entry, place point and the mark on the two dates
+that begin and end the range, and type `i b'. This command displays
+the end of your diary file in another window and inserts the block
+description; you can then type the diary entry.
+
+ "Cyclic" diary entries repeat after a fixed interval of days. To
+create one, select the starting date and use the `i c' command. The
+command prompts for the length of interval, then inserts the entry,
+which looks like this:
+
+ %%(diary-cyclic 50 3 1 1990) Renew medication
+
+This entry applies to March 1, 1990 and every 50th day following; `3 1
+1990' specifies the starting date. (If you are using the European
+calendar style, the month and day are interchanged.)
+
+ All three of these commands make marking diary entries. To insert a
+nonmarking entry, give a numeric argument to the command. For example,
+`C-u i a' makes a nonmarking anniversary diary entry.
+
+ Marking sexp diary entries in the calendar is _extremely_
+time-consuming, since every date visible in the calendar window must be
+individually checked. So it's a good idea to make sexp diary entries
+nonmarking (with `&') when possible.
+
+ Another sophisticated kind of sexp entry, a "floating" diary entry,
+specifies a regularly occurring event by offsets specified in days,
+weeks, and months. It is comparable to a crontab entry interpreted by
+the `cron' utility. Here is a nonmarking, floating diary entry that
+applies to the last Thursday in November:
+
+ &%%(diary-float 11 4 -1) American Thanksgiving
+
+The 11 specifies November (the eleventh month), the 4 specifies Thursday
+(the fourth day of the week, where Sunday is numbered zero), and the -1
+specifies "last" (1 would mean "first", 2 would mean "second", -2 would
+mean "second-to-last", and so on). The month can be a single month or
+a list of months. Thus you could change the 11 above to `'(1 2 3)' and
+have the entry apply to the last Thursday of January, February, and
+March. If the month is `t', the entry applies to all months of the
+year.
+
+ The sexp feature of the diary allows you to specify diary entries
+based on any Emacs Lisp expression. You can use the library of built-in
+functions or you can write your own functions. The built-in functions
+include the ones shown in this section, plus a few others (*note Sexp
+Diary Entries::).
+
+ The generality of sexps lets you specify any diary entry that you can
+describe algorithmically. Suppose you get paid on the 21st of the month
+if it is a weekday, and to the Friday before if the 21st is on a
+weekend. The diary entry
+
+ &%%(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
+
+to just those dates. This example illustrates how the sexp can depend
+on the variable `date'; this variable is a list (MONTH DAY YEAR) that
+gives the Gregorian date for which the diary entries are being found.
+If the value of the sexp is `t', the entry applies to that date. If
+the sexp evaluates to `nil', the entry does _not_ apply to that date.
+
+\1f
+File: xemacs.info, Node: Calendar Customization, Prev: Diary, Up: Calendar/Diary
+
+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.
+* Daylight Savings:: Changing the default.
+* Diary Customizing:: Defaults you can set.
+* Hebrew/Islamic Entries:: How to obtain them.
+* Fancy Diary Display:: Enhancing the diary display, sorting entries.
+* Included Diary Files:: Sharing a common diary file.
+* Sexp Diary Entries:: Fancy things you can do.
+* Appt Customizing:: Customizing appointment reminders.
+
+\1f
+File: xemacs.info, Node: Calendar Customizing, Next: Holiday Customizing, Up: Calendar Customization
+
+Customizing the Calendar
+........................
+
+ If you set the variable `view-diary-entries-initially' to `t',
+calling up the calendar automatically displays the diary entries for
+the current date as well. The diary dates appear only if the current
+date is visible. If you add both of the following lines to your init
+file:
+
+ (setq view-diary-entries-initially t)
+ (calendar)
+
+this displays both the calendar and diary windows whenever you start
+Emacs. *Note Init File::.
+
+ Similarly, if you set the variable
+`view-calendar-holidays-initially' to `t', entering the calendar
+automatically displays a list of holidays for the current three-month
+period. The holiday list appears in a separate window.
+
+ You can set the variable `mark-diary-entries-in-calendar' to `t' in
+order to mark any dates with diary entries. This takes effect whenever
+the calendar window contents are recomputed. There are two ways of
+marking these dates: by changing the face (*note Faces::), if the
+display supports that, or by placing a plus sign (`+') beside the date
+otherwise.
+
+ Similarly, setting the variable `mark-holidays-in-calendar' to `t'
+marks holiday dates, either with a change of face or with an asterisk
+(`*').
+
+ The variable `calendar-holiday-marker' specifies how to mark a date
+as being a holiday. Its value may be a character to insert next to the
+date, or a face name to use for displaying the date. Likewise, the
+variable `diary-entry-marker' specifies how to mark a date that has
+diary entries. The calendar creates faces named `holiday-face' and
+`diary-face' for these purposes; those symbols are the default values
+of these variables, when Emacs supports multiple faces on your terminal.
+
+ The variable `calendar-load-hook' is a normal hook run when the
+calendar package is first loaded (before actually starting to display
+the calendar).
+
+ Starting the calendar runs the normal hook
+`initial-calendar-window-hook'. Recomputation of the calendar display
+does not run this hook. But if you leave the calendar with the `q'
+command and reenter it, the hook runs again.
+
+ The variable `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
+`calendar-star-date'.
+
+ (add-hook 'today-visible-calendar-hook 'calendar-star-date)
+
+Another standard hook function marks the current date, either by
+changing its face or by adding an asterisk. Here's how to use it:
+
+ (add-hook 'today-visible-calendar-hook 'calendar-mark-today)
+
+The variable `calendar-today-marker' specifies how to mark today's
+date. Its value should be a character to insert next to the date or a
+face name to use for displaying the date. A face named
+`calendar-today-face' is provided for this purpose; that symbol is the
+default for this variable when Emacs supports multiple faces on your
+terminal.
+
+A similar normal hook, `today-invisible-calendar-hook' is run if the
+current date is _not_ visible in the window.
+
+\1f
+File: xemacs.info, Node: Holiday Customizing, Next: Date Display Format, Prev: Calendar Customizing, Up: Calendar Customization
+
+Customizing the 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 (`general-holidays'), local holidays
+(`local-holidays'), Christian holidays (`christian-holidays'), Hebrew
+(Jewish) holidays (`hebrew-holidays'), Islamic (Moslem) holidays
+(`islamic-holidays'), and other holidays (`other-holidays').
+
+ The general holidays are, by default, holidays common throughout the
+United States. To eliminate these holidays, set `general-holidays' to
+`nil'.
+
+ There are no default local holidays (but sites may supply some). You
+can set the variable `local-holidays' to any list of holidays, as
+described below.
+
+ 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 `all-christian-calendar-holidays',
+`all-hebrew-calendar-holidays', or `all-islamic-calendar-holidays' to
+`t'. If you want to eliminate the religious holidays, set any or all
+of the corresponding variables `christian-holidays', `hebrew-holidays',
+and `islamic-holidays' to `nil'.
+
+ You can set the variable `other-holidays' to any list of holidays.
+This list, normally empty, is intended for individual use.
+
+ Each of the lists (`general-holidays', `local-holidays',
+`christian-holidays', `hebrew-holidays', `islamic-holidays', and
+`other-holidays') is a list of "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 STRING is always the name of the holiday, as
+a string.
+
+`(holiday-fixed MONTH DAY STRING)'
+ A fixed date on the Gregorian calendar. MONTH and DAY are
+ numbers, STRING is the name of the holiday.
+
+`(holiday-float MONTH DAYNAME K STRING)'
+ The Kth DAYNAME in MONTH on the Gregorian calendar (DAYNAME=0 for
+ Sunday, and so on); negative K means count back from the end of
+ the month. STRING is the name of the holiday.
+
+`(holiday-hebrew MONTH DAY STRING)'
+ A fixed date on the Hebrew calendar. MONTH and DAY are numbers,
+ STRING is the name of the holiday.
+
+`(holiday-islamic MONTH DAY STRING)'
+ A fixed date on the Islamic calendar. MONTH and DAY are numbers,
+ STRING is the name of the holiday.
+
+`(holiday-julian MONTH DAY STRING)'
+ A fixed date on the Julian calendar. MONTH and DAY are numbers,
+ STRING is the name of the holiday.
+
+`(holiday-sexp SEXP STRING)'
+ A date calculated by the Lisp expression SEXP. The expression
+ should use the variable `year' to compute and return the date of a
+ holiday, or `nil' if the holiday doesn't happen this year. The
+ value of SEXP must represent the date as a list of the form
+ `(MONTH DAY YEAR)'. STRING is the name of the holiday.
+
+`(if CONDITION HOLIDAY-FORM &optional HOLIDAY-FORM)'
+ A holiday that happens only if CONDITION is true.
+
+`(FUNCTION [ARGS])'
+ A list of dates calculated by the function FUNCTION, called with
+ arguments ARGS.
+
+ For example, suppose you want to add Bastille Day, celebrated in
+France on July 14. You can do this by adding the following line to
+your init file:
+
+ (setq other-holidays '((holiday-fixed 7 14 "Bastille Day")))
+
+ *Note Init File::.
+
+The holiday form `(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:
+
+ (holiday-float 8 1 4 "Hurricane Supplication Day")
+
+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,
+-1 the last occurrence, -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,
+
+ (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")))
+
+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 `if' or
+the `holiday-sexp' form. For example, American presidential elections
+occur on the first Tuesday after the first Monday in November of years
+divisible by 4:
+
+ (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"))
+
+or
+
+ (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"))
+
+ 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 `(eclipses)' to `other-holidays' and write an Emacs
+Lisp function `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:
+
+ (((6 27 1991) "Lunar Eclipse") ((7 11 1991) "Solar Eclipse") ... )
+
+\1f
+File: xemacs.info, Node: Date Display Format, Next: Time Display Format, Prev: Holiday Customizing, Up: Calendar Customization
+
+Date Display Format
+...................
+
+ You can customize the manner of displaying dates in the diary, in
+mode lines, and in messages by setting `calendar-date-display-form'.
+This variable holds a list of expressions that can involve the variables
+`month', `day', and `year', which are all numbers in string form, and
+`monthname' and `dayname', which are both alphabetic strings. In the
+American style, the default value of this list is as follows:
+
+ ((if dayname (concat dayname ", ")) monthname " " day ", " year)
+
+while in the European style this value is the default:
+
+ ((if dayname (concat dayname ", ")) day " " monthname " " year)
+
+ + The ISO standard date representation is this:
+
+ (year "-" month "-" day)
+
+This specifies a typical American format:
+
+ (month "/" day "/" (substring year -2))
+
+\1f
+File: xemacs.info, Node: Time Display Format, Next: Daylight Savings, Prev: Date Display Format, Up: Calendar Customization
+
+Time Display Format
+...................
+
+ 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 `am' or `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 `calendar-time-display-form'. This variable is a
+list of expressions that can involve the variables `12-hours',
+`24-hours', and `minutes', which are all numbers in string form, and
+`am-pm' and `time-zone', which are both alphabetic strings. The
+default value of `calendar-time-display-form' is as follows:
+
+ (12-hours ":" minutes am-pm
+ (if time-zone " (") time-zone (if time-zone ")"))
+
+Here is a value that provides European style times:
+
+ (24-hours ":" minutes
+ (if time-zone " (") time-zone (if time-zone ")"))
+
+gives military-style times like `21:07 (UT)' if time zone names are
+defined, and times like `21:07' if they are not.
+
+\1f
+File: xemacs.info, Node: Daylight Savings, Next: Diary Customizing, Prev: Time Display Format, Up: Calendar Customization
+
+Daylight Savings Time
+.....................
+
+ Emacs understands the difference between standard time and daylight
+savings time--the times given for sunrise, sunset, solstices,
+equinoxes, and the phases of the moon take that into account. The rules
+for daylight savings time vary from place to place and have also varied
+historically from year to year. To do the job properly, Emacs needs to
+know which rules to use.
+
+ Some operating systems keep track of the rules that apply to the
+place where you are; on these systems, Emacs gets the information it
+needs from the system automatically. If some or all of this
+information is missing, Emacs fills in the gaps with the rules
+currently used in Cambridge, Massachusetts. If the resulting rules are
+not what you want, you can tell Emacs the rules to use by setting
+certain variables.
+
+ If the default choice of rules is not appropriate for your location,
+you can tell Emacs the rules to use by setting the variables
+`calendar-daylight-savings-starts' and
+`calendar-daylight-savings-ends'. Their values should be Lisp
+expressions that refer to the variable `year', and evaluate to the
+Gregorian date on which daylight savings time starts or (respectively)
+ends, in the form of a list `(MONTH DAY YEAR)'. The values should be
+`nil' if your area does not use daylight savings time.
+
+ Emacs uses these expressions to determine the starting date of
+daylight savings time for the holiday list and for correcting times of
+day in the solar and lunar calculations.
+
+ The values for Cambridge, Massachusetts are as follows:
+
+ (calendar-nth-named-day 1 0 4 year)
+ (calendar-nth-named-day -1 0 10 year)
+
+That is, the first 0th day (Sunday) of the fourth month (April) in the
+year specified by `year', and the last Sunday of the tenth month
+(October) of that year. If daylight savings time were changed to start
+on October 1, you would set `calendar-daylight-savings-starts' to this:
+
+ (list 10 1 year)
+
+ For a more complex example, suppose daylight savings time begins on
+the first of Nisan on the Hebrew calendar. You should set
+`calendar-daylight-savings-starts' to this value:
+
+ (calendar-gregorian-from-absolute
+ (calendar-absolute-from-hebrew
+ (list 1 1 (+ year 3760))))
+
+because Nisan is the first month in the Hebrew calendar and the Hebrew
+year differs from the Gregorian year by 3760 at Nisan.
+
+ If there is no daylight savings time at your location, or if you want
+all times in standard time, set `calendar-daylight-savings-starts' and
+`calendar-daylight-savings-ends' to `nil'.
+
+ The variable `calendar-daylight-time-offset' specifies the
+difference between daylight savings time and standard time, measured in
+minutes. The value for Cambridge, Massachusetts is 60.
+
+ The two variables `calendar-daylight-savings-starts-time' and
+`calendar-daylight-savings-ends-time' specify the number of minutes
+after midnight local time when the transition to and from daylight
+savings time should occur. For Cambridge, Massachusetts both variables'
+values are 120.
+
+\1f