This is ../info/xemacs.info, produced by makeinfo version 4.0 from xemacs/xemacs.texi. INFO-DIR-SECTION XEmacs Editor START-INFO-DIR-ENTRY * XEmacs: (xemacs). XEmacs Editor. END-INFO-DIR-ENTRY This file documents the XEmacs editor. Copyright (C) 1985, 1986, 1988 Richard M. Stallman. Copyright (C) 1991, 1992, 1993, 1994 Lucid, Inc. Copyright (C) 1993, 1994 Sun Microsystems, Inc. Copyright (C) 1995 Amdahl Corporation. Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided also that the sections entitled "The GNU Manifesto", "Distribution" and "GNU General Public License" are included exactly as in the original, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this manual into another language, under the above conditions for modified versions, except that the sections entitled "The GNU Manifesto", "Distribution" and "GNU General Public License" may be included in a translation approved by the author instead of in the original English.  File: xemacs.info, Node: Mail Mode, Prev: Mail Headers, Up: Sending Mail Mail Mode ========= The major mode used in the `*mail*' buffer is Mail mode. Mail mode is similar to Text mode, but several commands are provided on the `C-c' prefix. These commands all deal specifically with editing or sending the message. `C-c C-s' Send the message, and leave the `*mail*' buffer selected (`mail-send'). `C-c C-c' Send the message, and select some other buffer (`mail-send-and-exit'). `C-c C-f C-t' Move to the `To' header field, creating one if there is none (`mail-to'). `C-c C-f C-s' Move to the `Subject' header field, creating one if there is none (`mail-subject'). `C-c C-f C-c' Move to the `CC' header field, creating one if there is none (`mail-cc'). `C-c C-w' Insert the file `~/.signature' at the end of the message text (`mail-signature'). `C-c C-y' Yank the selected message (`mail-yank-original'). `C-c C-q' Fill all paragraphs of yanked old messages, each individually (`mail-fill-yanked-message'). `' Pops up a menu of useful mail-mode commands. There are two ways to send a message. `C-c C-c' (`mail-send-and-exit') is the usual way to send the message. It sends the message and then deletes the window (if there is another window) or switches to another buffer. It puts the `*mail*' buffer at the lowest priority for automatic reselection, since you are finished with using it. `C-c C-s' (`mail-send') sends the message and marks the `*mail*' buffer unmodified, but leaves that buffer selected so that you can modify the message (perhaps with new recipients) and send it again. Mail mode provides some other special commands that are useful for editing the headers and text of the message before you send it. There are three commands defined to move point to particular header fields, all based on the prefix `C-c C-f' (`C-f' is for "field"). They are `C-c C-f C-t' (`mail-to') to move to the `To' field, `C-c C-f C-s' (`mail-subject') for the `Subject' field, and `C-c C-f C-c' (`mail-cc') for the `CC' field. These fields have special motion commands because they are edited most frequently. `C-c C-w' (`mail-signature') adds a standard piece of text at the end of the message to say more about who you are. The text comes from the file `.signature' in your home directory. When you use an Rmail command to send mail from the Rmail mail reader, you can use `C-c C-y' `mail-yank-original' inside the `*mail*' buffer to insert the text of the message you are replying to. Normally Rmail indents each line of that message four spaces and eliminates most header fields. A numeric argument specifies the number of spaces to indent. An argument of just `C-u' says not to indent at all and not to eliminate anything. `C-c C-y' always uses the current message from the `RMAIL' buffer, so you can insert several old messages by selecting one in `RMAIL', switching to `*mail*' and yanking it, then switching back to `RMAIL' to select another. After using `C-c C-y', you can use the command `C-c C-q' (`mail-fill-yanked-message') to fill the paragraphs of the yanked old message or messages. One use of `C-c C-q' fills all such paragraphs, each one separately. Clicking the right mouse button in a mail buffer pops up a menu of the above commands, for easy access. Turning on Mail mode (which `C-x m' does automatically) calls the value of `text-mode-hook', if it is not void or `nil', and then calls the value of `mail-mode-hook' if that is not void or `nil'.  File: xemacs.info, Node: Reading Mail, Next: Calendar/Diary, Prev: Sending Mail, Up: Top Reading Mail ************ XEmacs provides three separate mail-reading packages. Each one comes with its own manual, which is included standard with the XEmacs distribution. The recommended mail-reading package for new users is VM. VM works with standard Unix-mail-format folders and was designed as a replacement for the older Rmail. XEmacs also provides a sophisticated and comfortable front-end to the MH mail-processing system, called `mh-e'. Unlike in other mail programs, folders in MH are stored as file-system directories, with each message occupying one (numbered) file. This facilitates working with mail using shell commands, and many other features of MH are also designed to integrate well with the shell and with shell scripts. Keep in mind, however, that in order to use mh-e you must have the MH mail-processing system installed on your computer. Finally, XEmacs provides the Rmail package. Rmail is (currently) the only mail reading package distributed with FSF GNU Emacs, and is powerful in its own right. However, it stores mail folders in a special format called `Babyl', that is incompatible with all other frequently-used mail programs. A utility program is provided for converting Babyl folders to standard Unix-mail format; however, unless you already have mail in Babyl-format folders, you should consider using VM or mh-e instead. (If at times you have to use FSF Emacs, it is not hard to obtain and install VM for that editor.)  File: xemacs.info, Node: Calendar/Diary, Next: Sorting, Prev: Reading Mail, Up: Top Calendar Mode and the Diary =========================== Emacs provides the functions of a desk calendar, with a diary of planned or past events. To enter the calendar, type `M-x calendar'; this displays a three-month calendar centered on the current month, with point on the current date. With a numeric argument, as in `C-u M-x calendar', it prompts you for the month and year to be the center of the three-month calendar. The calendar uses its own buffer, whose major mode is Calendar mode. `Button2' in the calendar brings up a menu of operations on a particular date; `Buttons3' brings up a menu of commonly used calendar features that are independent of any particular date. To exit the calendar, type `q'. *Note Customizing the Calendar and Diary: (elisp)Calendar, for customization information about the calendar and diary. * Menu: * Calendar Motion:: Moving through the calendar; selecting a date. * Scroll Calendar:: Bringing earlier or later months onto the screen. * Mark and Region:: Remembering dates, the mark ring. * General Calendar:: Exiting or recomputing the calendar. * LaTeX Calendar:: Print a calendar using LaTeX. * Holidays:: Displaying dates of holidays. * Sunrise/Sunset:: Displaying local times of sunrise and sunset. * Lunar Phases:: Displaying phases of the moon. * Other Calendars:: Converting dates to other calendar systems. * Diary:: Displaying events from your diary. * Calendar Customization:: Altering the behavior of the features above.  File: xemacs.info, Node: Calendar Motion, Next: Scroll Calendar, Prev: Calendar/Diary, Up: Calendar/Diary Movement in the Calendar ------------------------ Calendar mode lets you move through the calendar in logical units of time such as days, weeks, months, and years. If you move outside the three months originally displayed, the calendar display "scrolls" automatically through time to make the selected date visible. Moving to a date lets you view its holidays or diary entries, or convert it to other calendars; moving longer time periods is also useful simply to scroll the calendar. * Menu: * Calendar Unit Motion:: Moving by days, weeks, months, and years. * Move to Beginning or End:: Moving to start/end of weeks, months, and years. * Specified Dates:: Moving to the current date or another specific date.  File: xemacs.info, Node: Calendar Unit Motion, Next: Move to Beginning or End, Prev: Calendar Motion, Up: Calendar Motion Motion by Integral Days, Weeks, Months, Years ............................................. The commands for movement in the calendar buffer parallel the commands for movement in text. You can move forward and backward by days, weeks, months, and years. `C-f' Move point one day forward (`calendar-forward-day'). `C-b' Move point one day backward (`calendar-backward-day'). `C-n' Move point one week forward (`calendar-forward-week'). `C-p' Move point one week backward (`calendar-backward-week'). `M-}' Move point one month forward (`calendar-forward-month'). `M-{' Move point one month backward (`calendar-backward-month'). `C-x ]' Move point one year forward (`calendar-forward-year'). `C-x [' Move point one year backward (`calendar-backward-year'). The day and week commands are natural analogues of the usual Emacs commands for moving by characters and by lines. Just as `C-n' usually moves to the same column in the following line, in Calendar mode it moves to the same day in the following week. And `C-p' moves to the same day in the previous week. The arrow keys are equivalent to `C-f', `C-b', `C-n' and `C-p', just as they normally are in other modes. The commands for motion by months and years work like those for weeks, but move a larger distance. The month commands `M-}' and `M-{' move forward or backward by an entire month's time. The year commands `C-x ]' and `C-x [' move forward or backward a whole year. The easiest way to remember these commands is to consider months and years analogous to paragraphs and pages of text, respectively. But the commands themselves are not quite analogous. The ordinary Emacs paragraph commands move to the beginning or end of a paragraph, whereas these month and year commands move by an entire month or an entire year, which usually involves skipping across the end of a month or year. All these commands accept a numeric argument as a repeat count. For convenience, the digit keys and the minus sign specify numeric arguments in Calendar mode even without the Meta modifier. For example, `100 C-f' moves point 100 days forward from its present location.  File: xemacs.info, Node: Move to Beginning or End, Next: Specified Dates, Prev: Calendar Unit Motion, Up: Calendar Motion Beginning or End of Week, Month or Year ....................................... A week (or month, or year) is not just a quantity of days; we think of weeks (months, years) as starting on particular dates. So Calendar mode provides commands to move to the beginning or end of a week, month or year: `C-a' Move point to start of week (`calendar-beginning-of-week'). `C-e' Move point to end of week (`calendar-end-of-week'). `M-a' Move point to start of month (`calendar-beginning-of-month'). `M-e' Move point to end of month (`calendar-end-of-month'). `M-<' Move point to start of year (`calendar-beginning-of-year'). `M->' Move point to end of year (`calendar-end-of-year'). These commands also take numeric arguments as repeat counts, with the repeat count indicating how many weeks, months, or years to move backward or forward. By default, weeks begin on Sunday. To make them begin on Monday instead, set the variable `calendar-week-start-day' to 1.  File: xemacs.info, Node: Specified Dates, Prev: Move to Beginning or End, Up: Calendar Motion Particular Dates ................ Calendar mode provides commands for moving to a particular date specified in various ways. `g d' Move point to specified date (`calendar-goto-date'). `o' Center calendar around specified month (`calendar-other-month'). `.' Move point to today's date (`calendar-goto-today'). `g d' (`calendar-goto-date') prompts for a year, a month, and a day of the month, and then moves to that date. Because the calendar includes all dates from the beginning of the current era, you must type the year in its entirety; that is, type `1990', not `90'. `o' (`calendar-other-month') prompts for a month and year, then centers the three-month calendar around that month. You can return to today's date with `.' (`calendar-goto-today').  File: xemacs.info, Node: Scroll Calendar, Next: Mark and Region, Prev: Calendar Motion, Up: Calendar/Diary Scrolling the Calendar through Time ----------------------------------- The calendar display scrolls automatically through time when you move out of the visible portion. You can also scroll it manually. Imagine that the calendar window contains a long strip of paper with the months on it. Scrolling it means moving the strip so that new months become visible in the window. `C-x <' Scroll calendar one month forward (`scroll-calendar-left'). `C-x >' Scroll calendar one month backward (`scroll-calendar-right'). `C-v' `' Scroll calendar three months forward (`scroll-calendar-left-three-months'). `M-v' `' Scroll calendar three months backward (`scroll-calendar-right-three-months'). The most basic calendar scroll commands scroll by one month at a time. This means that there are two months of overlap between the display before the command and the display after. `C-x <' scrolls the calendar contents one month to the left; that is, it moves the display forward in time. `C-x >' scrolls the contents to the right, which moves backwards in time. The commands `C-v' and `M-v' scroll the calendar by an entire "screenful"--three months--in analogy with the usual meaning of these commands. `C-v' makes later dates visible and `M-v' makes earlier dates visible. These commands take a numeric argument as a repeat count; in particular, since `C-u' multiplies the next command by four, typing `C-u C-v' scrolls the calendar forward by a year and typing `C-u M-v' scrolls the calendar backward by a year. The function keys and are equivalent to `C-v' and `M-v', just as they are in other modes.  File: xemacs.info, Node: Mark and Region, Next: General Calendar, Prev: Scroll Calendar, Up: Calendar/Diary The Mark and the Region ----------------------- The concept of the mark applies to the calendar just as to any other buffer, but it marks a _date_, not a _position_ in the buffer. The region consists of the days between the mark and point (including the starting and stopping dates). `C-SPC' Set the mark to today's date (`calendar-set-mark'). `C-@' The same. `C-x C-x' Interchange mark and point (`calendar-exchange-point-and-mark'). `M-=' Display the number of days in the current region (`calendar-count-days-region'). You set the mark in the calendar, as in any other buffer, by using `C-@' or `C-SPC' (`calendar-set-mark'). You return to the marked date with the command `C-x C-x' (`calendar-exchange-point-and-mark') which puts the mark where point was and point where mark was. The calendar is scrolled as necessary, if the marked date was not visible on the screen. This does not change the extent of the region. To determine the number of days in the region, type `M-=' (`calendar-count-days-region'). The numbers of days printed is _inclusive_; that is, it includes the days specified by mark and point. The main use of the mark in the calendar is to remember dates that you may want to go back to. To make this feature more useful, the mark ring (*note Mark Ring::) operates exactly as in other buffers: Emacs remembers 16 previous locations of the mark. To return to a marked date, type `C-u C-SPC' (or `C-u C-@'); this is the command `calendar-set-mark' given a numeric argument. It moves point to where the mark was, restores the mark from the ring of former marks, and stores the previous point at the end of the mark ring. So, repeated use of this command moves point through all the old marks on the ring, one by one.  File: xemacs.info, Node: General Calendar, Next: LaTeX Calendar, Prev: Mark and Region, Up: Calendar/Diary Miscellaneous Calendar Commands ------------------------------- `p d' Display day-in-year (`calendar-print-day-of-year'). `?' Briefly describe calendar commands (`describe-calendar-mode'). `C-c C-l' Regenerate the calendar window (`redraw-calendar'). `SPC' Scroll the next window (`scroll-other-window'). `q' Exit from calendar (`exit-calendar'). If you want to know how many days have elapsed since the start of the year, or the number of days remaining in the year, type the `p d' command (`calendar-print-day-of-year'). This displays both of those numbers in the echo area. To display a brief description of the calendar commands, type `?' (`describe-calendar-mode'). For a fuller description, type `C-h m'. You can use `SPC' (`scroll-other-window') to scroll the other window. This is handy when you display a list of holidays or diary entries in another window. If the calendar window text gets corrupted, type `C-c C-l' (`redraw-calendar') to redraw it. (This can only happen if you use non-Calendar-mode editing commands.) In Calendar mode, you can use `SPC' (`scroll-other-window') to scroll the other window. This is handy when you display a list of holidays or diary entries in another window. To exit from the calendar, type `q' (`exit-calendar'). This buries all buffers related to the calendar, selecting other buffers. (If a frame contains a dedicated calendar window, exiting from the calendar iconifies that frame.)  File: xemacs.info, Node: LaTeX Calendar, Next: Holidays, Prev: General Calendar, Up: Calendar/Diary LaTeX Calendar ============== The Calendar LaTeX commands produce a buffer of LaTeX code that prints as a calendar. Depending on the command you use, the printed calendar covers the day, week, month or year that point is in. `t m' Generate a one-month calendar (`cal-tex-cursor-month'). `t M' Generate a sideways-printing one-month calendar (`cal-tex-cursor-month-landscape'). `t d' Generate a one-day calendar (`cal-tex-cursor-day'). `t w 1' Generate a one-page calendar for one week (`cal-tex-cursor-week'). `t w 2' Generate a two-page calendar for one week (`cal-tex-cursor-week2'). `t w 3' Generate an ISO-style calendar for one week (`cal-tex-cursor-week-iso'). `t w 4' Generate a calendar for one Monday-starting week (`cal-tex-cursor-week-monday'). `t f w' Generate a Filofax-style two-weeks-at-a-glance calendar (`cal-tex-cursor-filofax-2week'). `t f W' Generate a Filofax-style one-week-at-a-glance calendar (`cal-tex-cursor-filofax-week'). `t y' Generate a calendar for one year (`cal-tex-cursor-year'). `t Y' Generate a sideways-printing calendar for one year (`cal-tex-cursor-year-landscape'). `t f y' Generate a Filofax-style calendar for one year (`cal-tex-cursor-filofax-year'). Some of these commands print the calendar sideways (in "landscape mode"), so it can be wider than it is long. Some of them use Filofax paper size (3.75in x 6.75in). All of these commands accept a prefix argument which specifies how many days, weeks, months or years to print (starting always with the selected one). If the variable `cal-tex-holidays' is non-`nil' (the default), then the printed calendars show the holidays in `calendar-holidays'. If the variable `cal-tex-diary' is non-`nil' (the default is `nil'), diary entries are included also (in weekly and monthly calendars only).  File: xemacs.info, Node: Holidays, Next: Sunrise/Sunset, Prev: LaTeX Calendar, Up: Calendar/Diary Holidays -------- The Emacs calendar knows about all major and many minor holidays, and can display them. `h' Display holidays for the selected date (`calendar-cursor-holidays'). `Button2 Holidays' Display any holidays for the date you click on. `x' Mark holidays in the calendar window (`mark-calendar-holidays'). `u' Unmark calendar window (`calendar-unmark'). `a' List all holidays for the displayed three months in another window (`list-calendar-holidays'). `M-x holidays' List all holidays for three months around today's date in another window. `M-x list-holidays' List holidays in another window for a specified range of years. To see if any holidays fall on a given date, position point on that date in the calendar window and use the `h' command. Alternatively, click on that date with `Button2' and then choose `Holidays' from the menu that appears. Either way, this displays the holidays for that date, in the echo area if they fit there, otherwise in a separate window. To view the distribution of holidays for all the dates shown in the calendar, use the `x' command. This displays the dates that are holidays in a different face (or places a `*' after these dates, if display with multiple faces is not available). The command applies both to the currently visible months and to other months that subsequently become visible by scrolling. To turn marking off and erase the current marks, type `u', which also erases any diary marks (*note Diary::). To get even more detailed information, use the `a' command, which displays a separate buffer containing a list of all holidays in the current three-month range. You can use in the calendar window to scroll that list. The command `M-x holidays' displays the list of holidays for the current month and the preceding and succeeding months; this works even if you don't have a calendar window. If you want the list of holidays centered around a different month, use `C-u M-x holidays', which prompts for the month and year. The holidays known to Emacs include United States holidays and the major Christian, Jewish, and Islamic holidays; also the solstices and equinoxes. The command `M-x list-holidays' displays the list of holidays for a range of years. This function asks you for the starting and stopping years, and allows you to choose all the holidays or one of several categories of holidays. You can use this command even if you don't have a calendar window. The dates used by Emacs for holidays are based on _current practice_, not historical fact. Historically, for instance, the start of daylight savings time and even its existence have varied from year to year, but present United States law mandates that daylight savings time begins on the first Sunday in April. When the daylight savings rules are set up for the United States, Emacs always uses the present definition, even though it is wrong for some prior years.  File: xemacs.info, Node: Sunrise/Sunset, Next: Lunar Phases, Prev: Holidays, Up: Calendar/Diary Times of Sunrise and Sunset --------------------------- Special calendar commands can tell you, to within a minute or two, the times of sunrise and sunset for any date. `S' Display times of sunrise and sunset for the selected date (`calendar-sunrise-sunset'). `Button2 Sunrise/Sunset' Display times of sunrise and sunset for the date you click on. `M-x sunrise-sunset' Display times of sunrise and sunset for today's date. `C-u M-x sunrise-sunset' Display times of sunrise and sunset for a specified date. Within the calendar, to display the _local times_ of sunrise and sunset in the echo area, move point to the date you want, and type `S'. Alternatively, click `Button2' on the date, then choose `Sunrise/Sunset' from the menu that appears. The command `M-x sunrise-sunset' is available outside the calendar to display this information for today's date or a specified date. To specify a date other than today, use `C-u M-x sunrise-sunset', which prompts for the year, month, and day. You can display the times of sunrise and sunset for any location and any date with `C-u C-u M-x sunrise-sunset'. This asks you for a longitude, latitude, number of minutes difference from Coordinated Universal Time, and date, and then tells you the times of sunrise and sunset for that location on that date. Because the times of sunrise and sunset depend on the location on earth, you need to tell Emacs your latitude, longitude, and location name before using these commands. Here is an example of what to set: (setq calendar-latitude 40.1) (setq calendar-longitude -88.2) (setq calendar-location-name "Urbana, IL") Use one decimal place in the values of `calendar-latitude' and `calendar-longitude'. Your time zone also affects the local time of sunrise and sunset. Emacs usually gets time zone information from the operating system, but if these values are not what you want (or if the operating system does not supply them), you must set them yourself. Here is an example: (setq calendar-time-zone -360) (setq calendar-standard-time-zone-name "CST") (setq calendar-daylight-time-zone-name "CDT") The value of `calendar-time-zone' is the number of minutes difference between your local standard time and Coordinated Universal Time (Greenwich time). The values of `calendar-standard-time-zone-name' and `calendar-daylight-time-zone-name' are the abbreviations used in your time zone. Emacs displays the times of sunrise and sunset _corrected for daylight savings time_. *Note Daylight Savings::, for how daylight savings time is determined. As a user, you might find it convenient to set the calendar location variables for your usual physical location in your init file. And when you install Emacs on a machine, you can create a `default.el' file which sets them properly for the typical location of most users of that machine. *Note Init File::.  File: xemacs.info, Node: Lunar Phases, Next: Other Calendars, Prev: Sunrise/Sunset, Up: Calendar/Diary Phases of the Moon ------------------ These calendar commands display the dates and times of the phases of the moon (new moon, first quarter, full moon, last quarter). This feature is useful for debugging problems that "depend on the phase of the moon." `M' Display the dates and times for all the quarters of the moon for the three-month period shown (`calendar-phases-of-moon'). `M-x phases-of-moon' Display dates and times of the quarters of the moon for three months around today's date. Within the calendar, use the `M' command to display a separate buffer of the phases of the moon for the current three-month range. The dates and times listed are accurate to within a few minutes. Outside the calendar, use the command `M-x phases-of-moon' to display the list of the phases of the moon for the current month and the preceding and succeeding months. For information about a different month, use `C-u M-x phases-of-moon', which prompts for the month and year. The dates and times given for the phases of the moon are given in local time (corrected for daylight savings, when appropriate); but if the variable `calendar-time-zone' is void, Coordinated Universal Time (the Greenwich time zone) is used. *Note Daylight Savings::.  File: xemacs.info, Node: Other Calendars, Next: Calendar Systems, Prev: Lunar Phases, Up: Calendar/Diary Conversion To and From Other Calendars -------------------------------------- The Emacs calendar displayed is _always_ the Gregorian calendar, sometimes called the "new style" calendar, which is used in most of the world today. However, this calendar did not exist before the sixteenth century and was not widely used before the eighteenth century; it did not fully displace the Julian calendar and gain universal acceptance until the early twentieth century. The Emacs calendar can display any month since January, year 1 of the current era, but the calendar displayed is the Gregorian, even for a date at which the Gregorian calendar did not exist. While Emacs cannot display other calendars, it can convert dates to and from several other calendars. * Menu: * Calendar Systems:: The calendars Emacs understands (aside from Gregorian). * To Other Calendar:: Converting the selected date to various calendars. * From Other Calendar:: Moving to a date specified in another calendar. * Mayan Calendar:: Moving to a date specified in a Mayan calendar. If you are interested in these calendars, you can convert dates one at a time. Put point on the desired date of the Gregorian calendar and press the appropriate keys. The `p' is a mnemonic for "print" since Emacs "prints' the equivalent date in the echo area.  File: xemacs.info, Node: Calendar Systems, Next: To Other Calendar, Prev: Other Calendars, Up: Other Calendars Supported Calendar Systems ========================== The ISO commercial calendar is used largely in Europe. The Julian calendar, named after Julius Caesar, was the one used in Europe throughout medieval times, and in many countries up until the nineteenth century. Astronomers use a simple counting of days elapsed since noon, Monday, January 1, 4713 B.C. on the Julian calendar. The number of days elapsed is called the _Julian day number_ or the _Astronomical day number_. The Hebrew calendar is used by tradition in the Jewish religion. The Emacs calendar program uses the Hebrew calendar to determine the dates of Jewish holidays. Hebrew calendar dates begin and end at sunset. The Islamic calendar is used in many predominantly Islamic countries. Emacs uses it to determine the dates of Islamic holidays. There is no universal agreement in the Islamic world about the calendar; Emacs uses a widely accepted version, but the precise dates of Islamic holidays often depend on proclamation by religious authorities, not on calculations. As a consequence, the actual dates of observance can vary slightly from the dates computed by Emacs. Islamic calendar dates begin and end at sunset. The French Revolutionary calendar was created by the Jacobins after the 1789 revolution, to represent a more secular and nature-based view of the annual cycle, and to install a 10-day week in a rationalization measure similar to the metric system. The French government officially abandoned this calendar at the end of 1805. The Maya of Central America used three separate, overlapping calendar systems, the _long count_, the _tzolkin_, and the _haab_. Emacs knows about all three of these calendars. Experts dispute the exact correlation between the Mayan calendar and our calendar; Emacs uses the Goodman-Martinez-Thompson correlation in its calculations. The Copts use a calendar based on the ancient Egyptian solar calendar. Their calendar consists of twelve 30-day months followed by an extra five-day period. Once every fourth year they add a leap day to this extra period to make it six days. The Ethiopic calendar is identical in structure, but has different year numbers and month names. The Persians use a solar calendar based on a design of Omar Khayyam. Their calendar consists of twelve months of which the first six have 31 days, the next five have 30 days, and the last has 29 in ordinary years and 30 in leap years. Leap years occur in a complicated pattern every four or five years. The Chinese calendar is a complicated system of lunar months arranged into solar years. The years go in cycles of sixty, each year containing either twelve months in an ordinary year or thirteen months in a leap year; each month has either 29 or 30 days. Years, ordinary months, and days are named by combining one of ten "celestial stems" with one of twelve "terrestrial branches" for a total of sixty names that are repeated in a cycle of sixty.  File: xemacs.info, Node: To Other Calendar, Next: From Other Calendar, Prev: Calendar Systems, Up: Other Calendars Converting To Other Calendars ============================= The following commands describe the selected date (the date at point) in various other calendar systems: `Button2 Other Calendars' Display the date that you click on, expressed in various other calendars. `p c' Display ISO commercial calendar equivalent for selected day (`calendar-print-iso-date'). `p j' Display Julian date for selected day (`calendar-print-julian-date'). `p a' Display astronomical (Julian) day number for selected day (`calendar-print-astro-day-number'). `p h' Display Hebrew date for selected day (`calendar-print-hebrew-date'). `p i' Display Islamic date for selected day (`calendar-print-islamic-date'). `p f' Display French Revolutionary date for selected day (`calendar-print-french-date'). `p C' Display Chinese date for selected day (`calendar-print-chinese-date'). `p k' Display Coptic date for selected day (`calendar-print-coptic-date'). `p e' Display Ethiopic date for selected day (`calendar-print-ethiopic-date'). `p p' Display Persian date for selected day (`calendar-print-persian-date'). `p m' Display Mayan date for selected day (`calendar-print-mayan-date'). If you are using X, the easiest way to translate a date into other calendars is to click on it with `Button2', then choose `Other Calendars' from the menu that appears. This displays the equivalent forms of the date in all the calendars Emacs understands, in the form of a menu. (Choosing an alternative from this menu doesn't actually do anything--the menu is used only for display.) Put point on the desired date of the Gregorian calendar, then type the appropriate keys. The `p' is a mnemonic for "print" since Emacs "prints" the equivalent date in the echo area.  File: xemacs.info, Node: From Other Calendar, Next: Mayan Calendar, Prev: To Other Calendar, Up: Other Calendars Converting From Other Calendars =============================== You can use the other supported calendars to specify a date to move to. This section describes the commands for doing this using calendars other than Mayan; for the Mayan calendar, see the following section. `g c' Move to a date specified in the ISO commercial calendar (`calendar-goto-iso-date'). `g j' Move to a date specified in the Julian calendar (`calendar-goto-julian-date'). `g a' Move to a date specified in astronomical (Julian) day number (`calendar-goto-astro-day-number'). `g h' Move to a date specified in the Hebrew calendar (`calendar-goto-hebrew-date'). `g i' Move to a date specified in the Islamic calendar (`calendar-goto-islamic-date'). `g f' Move to a date specified in the French Revolutionary calendar (`calendar-goto-french-date'). `g C' Move to a date specified in the Chinese calendar (`calendar-goto-chinese-date'). `g p' Move to a date specified in the Persian calendar (`calendar-goto-persian-date'). `g k' Move to a date specified in the Coptic calendar (`calendar-goto-coptic-date'). `g e' Move to a date specified in the Ethiopic calendar (`calendar-goto-ethiopic-date'). These commands ask you for a date on the other calendar, move point to the Gregorian calendar date equivalent to that date, and display the other calendar's date in the echo area. Emacs uses strict completion (*note Completion::) whenever it asks you to type a month name, so you don't have to worry about the spelling of Hebrew, Islamic, or French names. One common question concerning the Hebrew calendar is the computation of the anniversary of a date of death, called a "yahrzeit." The Emacs calendar includes a facility for such calculations. If you are in the calendar, the command `M-x list-yahrzeit-dates' asks you for a range of years and then displays a list of the yahrzeit dates for those years for the date given by point. If you are not in the calendar, this command first asks you for the date of death and the range of years, and then displays the list of yahrzeit dates.  File: xemacs.info, Node: Mayan Calendar, Next: Diary, Prev: From Other Calendar, Up: Other Calendars Converting from the Mayan Calendar ---------------------------------- Here are the commands to select dates based on the Mayan calendar: `g m l' Move to a date specified by the long count calendar (`calendar-goto-mayan-long-count-date'). `g m n t' Move to the next occurrence of a place in the tzolkin calendar (`calendar-next-tzolkin-date'). `g m p t' Move to the previous occurrence of a place in the tzolkin calendar (`calendar-previous-tzolkin-date'). `g m n h' Move to the next occurrence of a place in the haab calendar (`calendar-next-haab-date'). `g m p h' Move to the previous occurrence of a place in the haab calendar (`calendar-previous-haab-date'). `g m n c' Move to the next occurrence of a place in the calendar round (`calendar-next-calendar-round-date'). `g m p c' Move to the previous occurrence of a place in the calendar round (`calendar-previous-calendar-round-date'). To understand these commands, you need to understand the Mayan calendars. The "long count" is a counting of days with these units: 1 kin = 1 day 1 uinal = 20 kin 1 tun = 18 uinal 1 katun = 20 tun 1 baktun = 20 katun Thus, the long count date 12.16.11.16.6 means 12 baktun, 16 katun, 11 tun, 16 uinal, and 6 kin. The Emacs calendar can handle Mayan long count dates as early as 7.17.18.13.1, but no earlier. When you use the `g m l' command, type the Mayan long count date with the baktun, katun, tun, uinal, and kin separated by periods. The Mayan tzolkin calendar is a cycle of 260 days formed by a pair of independent cycles of 13 and 20 days. Since this cycle repeats endlessly, Emacs provides commands to move backward and forward to the previous or next point in the cycle. Type `g m p t' to go to the previous tzolkin date; Emacs asks you for a tzolkin date and moves point to the previous occurrence of that date. Similarly, type `g m n t' to go to the next occurrence of a tzolkin date. The Mayan haab calendar is a cycle of 365 days arranged as 18 months of 20 days each, followed a 5-day monthless period. Like the tzolkin cycle, this cycle repeats endlessly, and there are commands to move backward and forward to the previous or next point in the cycle. Type `g m p h' to go to the previous haab date; Emacs asks you for a haab date and moves point to the previous occurrence of that date. Similarly, type `g m n h' to go to the next occurrence of a haab date. The Maya also used the combination of the tzolkin date and the haab date. This combination is a cycle of about 52 years called a _calendar round_. If you type `g m p c', Emacs asks you for both a haab and a tzolkin date and then moves point to the previous occurrence of that combination. Use `g m n c' to move point to the next occurrence of a combination. These commands signal an error if the haab/tzolkin date combination you have typed is impossible. Emacs uses strict completion (*note Completion::) whenever it asks you to type a Mayan name, so you don't have to worry about spelling.  File: xemacs.info, Node: Diary, Next: Calendar Customization, Prev: Mayan Calendar, Up: Calendar/Diary The Diary --------- The Emacs diary keeps track of appointments or other events on a daily basis, in conjunction with the calendar. To use the diary feature, you must first create a "diary file" containing a list of events and their dates. Then Emacs can automatically pick out and display the events for today, for the immediate future, or for any specified date. By default, Emacs uses `~/diary' as the diary file. This is the same file that the `calendar' utility uses. A sample `~/diary' file is: 12/22/1988 Twentieth wedding anniversary!! &1/1. Happy New Year! 10/22 Ruth's birthday. * 21, *: Payday Tuesday--weekly meeting with grad students at 10am Supowit, Shen, Bitner, and Kapoor to attend. 1/13/89 Friday the thirteenth!! &thu 4pm squash game with Lloyd. mar 16 Dad's birthday April 15, 1989 Income tax due. &* 15 time cards due. This example uses extra spaces to align the event descriptions of most of the entries. Such formatting is purely a matter of taste. Although you probably will start by creating a diary manually, Emacs provides a number of commands to let you view, add, and change diary entries. You can also share diary entries with other users (*note Included Diary Files::). * Menu: * Diary Commands:: Viewing diary entries and associated calendar dates. * Format of Diary File:: Entering events in your diary. * Date Formats:: Various ways you can specify dates. * Adding to Diary:: Commands to create diary entries. * Special Diary Entries:: Anniversaries, blocks of dates, cyclic entries, etc.  File: xemacs.info, Node: Diary Commands, Next: Format of Diary File, Prev: Diary, Up: Diary Commands Displaying Diary Entries --------------------------------- Once you have created a `~/diary' file, you can use the calendar to view it. You can also view today's events outside of Calendar mode. `d' Display all diary entries for the selected date (`view-diary-entries'). `Button2 Diary' Display all diary entries for the date you click on. `s' Display the entire diary file (`show-all-diary-entries'). `m' Mark all visible dates that have diary entries (`mark-diary-entries'). `u' Unmark the calendar window (`calendar-unmark'). `M-x print-diary-entries' Print hard copy of the diary display as it appears. `M-x diary' Display all diary entries for today's date. `M-x diary-mail-entries' Mail yourself email reminders about upcoming diary entries. Displaying the diary entries with `d' shows in a separate window the diary entries for the selected date in the calendar. The mode line of the new window shows the date of the diary entries and any holidays that fall on that date. If you specify a numeric argument with `d', it shows all the diary entries for that many successive days. Thus, `2 d' displays all the entries for the selected date and for the following day. Another way to display the diary entries for a date is to click `Button2' on the date, and then choose `Diary' from the menu that appears. To get a broader view of which days are mentioned in the diary, use the `m' command. This displays the dates that have diary entries in a different face (or places a `+' after these dates, if display with multiple faces is not available). The command applies both to the currently visible months and to other months that subsequently become visible by scrolling. To turn marking off and erase the current marks, type `u', which also turns off holiday marks (*note Holidays::). To see the full diary file, rather than just some of the entries, use the `s' command. Display of selected diary entries uses the selective display feature to hide entries that don't apply. The diary buffer as you see it is an illusion, so simply printing the buffer does not print what you see on your screen. There is a special command to print hard copy of the diary buffer _as it appears_; this command is `M-x print-diary-entries'. It sends the data directly to the printer. You can customize it like `lpr-region' (*note Hardcopy::). The command `M-x diary' displays the diary entries for the current date, independently of the calendar display, and optionally for the next few days as well; the variable `number-of-diary-entries' specifies how many days to include (*note Customization::). If you put `(diary)' in your init file, this automatically displays a window with the day's diary entries, when you enter Emacs. *Note Init File::. The mode line of the displayed window shows the date and any holidays that fall on that date. Many users like to receive notice of events in their diary as email. To send such mail to yourself, use the command `M-x diary-mail-entries'. A prefix argument specifies how many days (starting with today) to check; otherwise, the variable `diary-mail-days' says how many days.  File: xemacs.info, Node: Format of Diary File, Next: Date Formats, Prev: Diary Commands, Up: Diary The Diary File -------------- Your "diary file" is a file that records events associated with particular dates. The name of the diary file is specified by the variable `diary-file'; `~/diary' is the default. The `calendar' utility program supports a subset of the format allowed by the Emacs diary facilities, so you can use that utility to view the diary file, with reasonable results aside from the entries it cannot understand. Each entry in the diary file describes one event and consists of one or more lines. An entry always begins with a date specification at the left margin. The rest of the entry is simply text to describe the event. If the entry has more than one line, then the lines after the first must begin with whitespace to indicate they continue a previous entry. Lines that do not begin with valid dates and do not continue a preceding entry are ignored. You can inhibit the marking of certain diary entries in the calendar window; to do this, insert an ampersand (`&') at the beginning of the entry, before the date. This has no effect on display of the entry in the diary window; it affects only marks on dates in the calendar window. Nonmarking entries are especially useful for generic entries that would otherwise mark many different dates. If the first line of a diary entry consists only of the date or day name with no following blanks or punctuation, then the diary window display doesn't include that line; only the continuation lines appear. For example, this entry: 02/11/1989 Bill B. visits Princeton today 2pm Cognitive Studies Committee meeting 2:30-5:30 Liz at Lawrenceville 4:00pm Dentist appt 7:30pm Dinner at George's 8:00-10:00pm concert appears in the diary window without the date line at the beginning. This style of entry looks neater when you display just a single day's entries, but can cause confusion if you ask for more than one day's entries. You can edit the diary entries as they appear in the window, but it is important to remember that the buffer displayed contains the _entire_ diary file, with portions of it concealed from view. This means, for instance, that the `C-f' (`forward-char') command can put point at what appears to be the end of the line, but what is in reality the middle of some concealed line. _Be careful when editing the diary entries!_ Inserting additional lines or adding/deleting characters in the middle of a visible line cannot cause problems, but editing at the end of a line may not do what you expect. Deleting a line may delete other invisible entries that follow it. Before editing the diary, it is best to display the entire file with `s' (`show-all-diary-entries').  File: xemacs.info, Node: Date Formats, Next: Adding to Diary, Prev: Format of Diary File, Up: Diary Date Formats ------------ Here are some sample diary entries, illustrating different ways of formatting a date. The examples all show dates in American order (month, day, year), but Calendar mode supports European order (day, month, year) as an option. 4/20/93 Switch-over to new tabulation system apr. 25 Start tabulating annual results 4/30 Results for April are due */25 Monthly cycle finishes Friday Don't leave without backing up files The first entry appears only once, on April 20, 1993. The second and third appear every year on the specified dates, and the fourth uses a wildcard (asterisk) for the month, so it appears on the 25th of every month. The final entry appears every week on Friday. You can use just numbers to express a date, as in `MONTH/DAY' or `MONTH/DAY/YEAR'. This must be followed by a nondigit. In the date itself, MONTH and DAY are numbers of one or two digits. The optional YEAR is also a number, and may be abbreviated to the last two digits; that is, you can use `11/12/1989' or `11/12/89'. Dates can also have the form `MONTHNAME DAY' or `MONTHNAME DAY, YEAR', where the month's name can be spelled in full or abbreviated to three characters (with or without a period). Case is not significant. A date may be "generic"; that is, partially unspecified. Then the entry applies to all dates that match the specification. If the date does not contain a year, it is generic and applies to any year. Alternatively, MONTH, DAY, or YEAR can be a `*'; this matches any month, day, or year, respectively. Thus, a diary entry `3/*/*' matches any day in March of any year; so does `march *'. If you prefer the European style of writing dates--in which the day comes before the month--type `M-x european-calendar' while in the calendar, or set the variable `european-calendar-style' to `t' _before_ using any calendar or diary command. This mode interprets all dates in the diary in the European manner, and also uses European style for displaying diary dates. (Note that there is no comma after the MONTHNAME in the European style.) To go back to the (default) American style of writing dates, type `M-x american-calendar'. You can use the name of a day of the week as a generic date which applies to any date falling on that day of the week. You can abbreviate the day of the week to three letters (with or without a period) or spell it in full; case is not significant.