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GNU Info File | 1994-10-05 | 48KB | 869 lines

This is Info file ../info/emacs, produced by Makeinfo-1.54 from the input file emacs.texi. File: emacs, Node: Dired Deletion, Next: Flagging Many Files, Prev: Dired Commands, Up: Dired Deleting Files with Dired ========================= The primary use of Dired is to "flag" files for deletion and then delete the files previously flagged. Flag this file for deletion. Remove deletion flag on this line. `DEL' Move point to previous line and remove the deletion flag on that line. Delete the files that are flagged for deletion. You can flag a file for deletion by moving to the line describing the file and typing `d'. The deletion flag is visible as a `D' at the beginning of the line. This command moves point to the next line, so that repeated `d' commands flag successive files. A numeric argument serves as a repeat count. The files are flagged for deletion rather than deleted immediately to reduce the danger of deleting a file accidentally. Until you direct Dired to expunge the flagged files, you can remove deletion flags using the commands `u' and DEL. `u' works just like `d', but removes flags rather than making flags. DEL moves upward, removing flags; it is like `u' with numeric argument automatically negated. To delete the flagged files, type `x' (`dired-expunge'). This command first displays a list of all the file names flagged for deletion, and requests confirmation with `yes'. If you confirm, Dired deletes the flagged files, then deletes their lines from the text of the Dired buffer. The shortened Dired buffer remains selected. If you answer `no' or quit with `C-g' when asked to confirm, you return immediately to Dired, with the deletion flags still present in the buffer, and no files actually deleted. File: emacs, Node: Flagging Many Files, Next: Dired Visiting, Prev: Dired Deletion, Up: Dired Flagging Many Files =================== Flag all auto-save files (files whose names start and end with `#') for deletion (*note Auto Save::.). Flag all backup files (files whose names end with `~') for deletion (*note Backup::.). `. (Period)' Flag excess numeric backup files for deletion. The oldest and newest few backup files of any one file are exempt; the middle ones are flagged. `% d REGEXP RET' Flag for deletion all files whose names match the regular expression REGEXP (`dired-flag-files-regexp'). `%d' is like `% m' except that it flags files with `D' instead of marking with `*'. *Note Marks vs Flags::. The `#', `~' and `.' commands flag many files for deletion, based on their file names. These commands are useful precisely because they do not actually delete any files; you can remove the deletion flags from any flagged files that you really wish to keep. `#' flags for deletion all files whose names look like auto-save files (*note Auto Save::.)--that is, files whose names begin and end with `#'. `~' flags for deletion all files whose names say they are backup files (*note Backup::.)--that is, whose names end in `~'. `.' (Period) flags just some of the backup files for deletion: all but the oldest few and newest few backups of any one file. Normally `dired-kept-versions' (*not* `kept-new-versions'; that applies only when saving) specifies the number of newest versions of each file to keep, and `kept-old-versions' specifies the number of oldest versions to keep. Period with a positive numeric argument, as in `C-u 3 .', specifies the number of newest versions to keep, overriding `dired-kept-versions'. A negative numeric argument overrides `kept-old-versions', using minus the value of the argument to specify the number of oldest versions of each file to keep. The `% d' command flags all files whose names match a specified regular expression (`dired-flag-files-regexp'). Only the non-directory part of the file name is used in matching. You can use `^' and `$' to anchor matches. You can exclude subdirectories by hiding them (*note Hiding Subdirectories::.). File: emacs, Node: Dired Visiting, Next: Marks vs Flags, Prev: Flagging Many Files, Up: Dired Visiting Files in Dired ======================= There are several Dired commands for visiting or examining the files listed in the Dired buffer. All of them apply to the current line's file; if that file is really a directory, these commands invoke Dired on that subdirectory (making a separate Dired buffer). Visit the file described on the current line, like typing `C-x C-f' and supplying that file name (`dired-find-file'). *Note Visiting::. Like `f', but uses another window to display the file's buffer (`dired-find-file-other-window'). The Dired buffer remains visible in the first window. This is like using `C-x 4 C-f' to visit the file. *Note Windows::. `C-o' Visit the file described on the current line, and display the buffer in another window, but do not select that window (`dired-display-file'). `Mouse-2' Visit the file named by the line you click on (`dired-mouse-find-file-other-window'). This uses another window to display the file, like the `o' command. View the file described on the current line, using `M-x view-file' (`dired-view-file'). Viewing a file is like visiting it, but is slanted toward moving around in the file conveniently and does not allow changing the file. *Note View File: Misc File Ops. File: emacs, Node: Marks vs Flags, Next: Operating on Files, Prev: Dired Visiting, Up: Dired Dired Marks vs. Flags ===================== Instead of flagging a file with `D', you can "mark" the file with some other character (usually `*'). Most Dired commands to operate on files, aside from "expunge" (`x'), look for files marked with `*'. Here are some commands for marking with `*' (and also for unmarking). (*Note Dired Deletion::, for commands to flag and unflag files.) Mark the current file with `*' (`dired-mark'). With a numeric argument N, mark the next N files starting with the current file. (If N is negative, mark the previous -N files.) Mark all executable files with `*' (`dired-mark-executables'). With a numeric argument, unmark all those files. Mark all symbolic links with `*' (`dired-mark-symlinks'). With a numeric argument, unmark all those files. Mark with `*' all files which are actually directories, except for `.' and `..' (`dired-mark-directories'). With a numeric argument, unmark all those files. `M-DEL MARKCHAR' Remove all marks that use the character MARKCHAR (`dired-unmark-all-files'). If you specify RET as MARKCHAR, this command removes all marks, no matter what the marker character is. With a numeric argument, this command queries about each marked file, asking whether to remove its mark. You can answer `y' meaning yes, `n' meaning no, `!' to remove the marks from the remaining files without asking about them. `c OLD NEW' Replace all marks that use the character OLD with marks that use the character NEW (`dired-change-marks'). This command is the primary way to create or use marks other than `*' or `D'. The arguments are single characters--do not use RET to terminate them. You can use almost any character as a mark character by means of this command, to distinguish various classes of files. If OLD is a space (` '), then the command operates on all unmarked files; if NEW is a space, then the command unmarks the files it acts on. To illustrate the power of this command, here is how to put `*' marks on all the files that are unmarked, while unmarking all those that have `*' marks: c * t c SPC * c t SPC `% m REGEXP RET' Mark (with `*') all files whose names match the regular expression REGEXP (`dired-mark-files-regexp'). Only the non-directory part of the file name is used in matching. Use `^' and `$' to anchor matches. Exclude subdirectories by hiding them (*note Hiding Subdirectories::.). File: emacs, Node: Operating on Files, Next: Shell Commands in Dired, Prev: Marks vs Flags, Up: Dired Operating on Files ================== This section describes the basic Dired commands to operate on one file or several files. All of these commands are capital letters; all of them use the minibuffer, either to read an argument or to ask for confirmation, before they act. All use the following convention to decide which files to manipulate: * If you give the command a numeric prefix argument N, it operates on the next N files, starting with the current file. (If N is negative, the command operates on the -N files preceding the current line.) * Otherwise, if some files are marked with `*', the command operates on all those files. * Otherwise, the command operates on the current file only. Here are the file-manipulating commands that operate on files in this way. (Some other Dired commands, such as `!' and the `%' commands, use the same conventions to decide which files to work on.) `C NEW RET' Copy the specified files (`dired-do-copy'). The argument NEW is the directory to copy into, or (if copying a single file) the new name. If `dired-copy-preserve-time' is non-`nil', then copying with this command sets the modification time of the new file to be the same as that of the old file. `R NEW RET' Rename the specified files (`dired-do-rename'). The argument NEW is the directory to rename into, or (if renaming a single file) the new name. Dired automatically changes the visited file name of buffers associated with renamed files so that they refer to the new names. `H NEW RET' Make hard links to the specified files (`dired-do-hardlink'). The argument NEW is the directory to make the links in, or (if making just one link) the name to give the link. `S NEW RET' Make symbolic links to the specified files (`dired-do-symlink'). The argument NEW is the directory to make the links in, or (if making just one link) the name to give the link. `M MODESPEC RET' Change the mode (also called "permission bits") of the specified files (`dired-do-chmod'). This uses the `chmod' program, so MODESPEC can be any argument that `chmod' can handle. `G NEWGROUP RET' Change the group of the specified files to NEWGROUP (`dired-do-chgrp'). `O NEWOWNER RET' Change the owner of the specified files to NEWOWNER (`dired-do-chown'). (On most systems, only the superuser can do this.) The variable `dired-chown-program' specifies the name of the program to use to do the work (different systems put `chown' in different places). `P COMMAND RET' Print the specified files (`dired-do-print'). You must specify the command to print them with, but the minibuffer starts out with a suitable guess made using the variables `lpr-command' and `lpr-switches' (the same variables that `lpr-file' uses; *note Hardcopy::.). Compress or uncompress the specified files (`dired-do-compress'). If the file appears to be a compressed file, it is uncompressed; otherwise, it is compressed. Load the specified Emacs Lisp files (`dired-do-load'). *Note Lisp Libraries::. Byte compile the specified Emacs Lisp files (`dired-do-byte-compile'). *Note Byte Compilation: (elisp)Byte Compilation. File: emacs, Node: Shell Commands in Dired, Next: Transforming File Names, Prev: Operating on Files, Up: Dired Shell Commands in Dired ======================= The dired command `!' (`dired-do-shell-command') reads a shell command string in the minibuffer and runs that shell command on all the specified files. There are two ways of applying a shell command to multiple files: * If you use `*' in the shell command, then it runs just once, with the list of file names substituted for the `*'. The order of file names is the order of appearance in the Dired buffer. Thus, `! tar cf foo.tar * RET' runs `tar' on the entire list of file names, putting them into one tar file `foo.tar'. * If the command string doesn't contain `*', then it runs once *for each file*, with the file name added at the end. For example, `! uudecode RET' runs `uudecode' on each file. What if you want to run the shell command once for each file but with the file name inserted in the middle? Or if you want to use the file names in a more complicated fashion? Use a shell loop. For example, this shell command would run `uuencode' on each of the specified files, writing the output into a corresponding `.uu' file: for file in *; uuencode $file $file >$file.uu; done The working directory for the shell command is the top level directory of the Dired buffer. The `!' command does not attempt to update the Dired buffer to show new or modified files, because it doesn't really understand shell commands, and does not know what files the shell command changed. Use the `g' command to update the Dired buffer (*note Dired Updating::.). File: emacs, Node: Transforming File Names, Next: Comparison in Dired, Prev: Shell Commands in Dired, Up: Dired Transforming File Names in Dired ================================ Here are commands that alter file names in a systematic way: `% u' Rename each of the selected files to an upper case name (`dired-upcase'). If the old file names are `Foo' and `bar', the new names are `FOO' and `BAR'. `% l' Rename each of the selected files to a lower case name (`dired-downcase'). If the old file names are `Foo' and `bar', the new names are `foo' and `bar'. `% R FROM RET TO RET' `% C FROM RET TO RET' `% H FROM RET TO RET' `% S FROM RET TO RET' These four commands rename, copy, make hard links and make soft links, in each case computing the new name by regular expression substitution from the name of the old file. The four regular expression substitution commands effectively perform `query-replace-regexp' on the selected file names in the Dired buffer. They read two arguments: a regular expression FROM, and a substitution pattern TO. The commands match each "old" file name against the regular expression FROM, and then replace the matching part with TO. You can use `\&' and `\DIGIT' in TO to refer to all or part of what the pattern matched in the old file name, as in `query-replace' (*note Query Replace::.). If the regular expression matches more than once in a file name, only the first match is replaced. For example, `% R ^.*$ RET x-\& RET' renames each selected file by prepending `x-' to its name. The inverse of this, removing `x-' from the front of each file name, is also possible: one method is `% R ^x-$.*$$ RET \1 RET'; another is `% R ^x- RET RET'. (Use `^' and `$' to anchor matches that should span the whole filename.) Normally, the replacement process does not consider the files' directory names; it operates on the file name within the directory. If you specify a numeric argument of zero, then replacement affects the entire absolute file name including directory name. Often you will want to apply the command to all files matching the same REGEXP that you use in the command. To do this, mark those files with `% m REGEXP RET', then use the same regular expression in the command to operate on the files. To make this easier, the `%' commands to operate on files use the last regular expression specified in any `%' command as a default. File: emacs, Node: Comparison in Dired, Next: Subdirectories in Dired, Prev: Transforming File Names, Up: Dired File Comparison with Dired ========================== Here are two Dired commands that compare specified files using `diff'. Compare the current file (the file at point) with another file (the file at the mark) using the `diff' program (`dired-diff'). The file at the mark is the first argument of `diff', and the file at point is the second argument. `M-=' Compare the current file with its latest backup file (`dired-backup-diff'). If the current file is itself a backup, compare it with the file it is a backup of; this way, you can compare a file with any backup version of your choice. The backup file is the first file given to `diff'. File: emacs, Node: Subdirectories in Dired, Next: Subdirectory Motion, Prev: Comparison in Dired, Up: Dired Subdirectories in Dired ======================= A Dired buffer displays just one directory in the normal case; but you can optionally include its subdirectories as well. The simplest way to include multiple directories in one Dired buffer is to specify the options `-lR' for running `ls'. (If you give a numeric argument when you run Dired, then you can specify these options in the minibuffer.) That produces a recursive directory listing showing all subdirectories at all levels. But usually all the subdirectories are too many; usually you will prefer to include specific subdirectories only. You can do this with the `i' command: Insert the contents of a subdirectory later in the buffer. Use the `i' (`dired-maybe-insert-subdir') command on a line that describes a file which is a directory. It inserts the contents of that directory into the same Dired buffer, and moves there. Inserted subdirectory contents follow the top-level directory of the Dired buffer, just as they do in `ls -lR' output. If the subdirectory's contents are already present in the buffer, the `i' command just moves to it. In either case, `i' sets the Emacs mark before moving, so `C-u C-SPC' takes you back to the old position in the buffer (the line describing that subdirectory). Use the `l' command (`dired-do-redisplay') to update the subdirectory's contents. Use `k' to delete the subdirectory. *Note Dired Updating::. File: emacs, Node: Subdirectory Motion, Next: Hiding Subdirectories, Prev: Subdirectories in Dired, Up: Dired Moving Over Subdirectories ========================== When a Dired buffer lists subdirectories, you can use the page motion commands `C-x [' and `C-x ]' to move by entire directories. The following commands move across, up and down in the tree of directories within one Dired buffer. They move to "directory header lines", which are the lines that give a directory's name, at the beginning of the directory's contents. `C-M-n' Go to next subdirectory header line, regardless of level (`dired-next-subdir'). `C-M-p' Go to previous subdirectory header line, regardless of level (`dired-prev-subdir'). `C-M-u' Go up to the parent directory's header line (`dired-tree-up'). `C-M-d' Go down in the directory tree, to the first subdirectory's header line (`dired-tree-down'). File: emacs, Node: Hiding Subdirectories, Next: Dired Updating, Prev: Subdirectory Motion, Up: Dired Hiding Subdirectories ===================== "Hiding" a subdirectory means to make it invisible, except for its header line, via selective display (*note Selective Display::.). Hide or reveal the subdirectory that point is in, and move point to the next subdirectory (`dired-hide-subdir'). A numeric argument serves as a repeat count. `M-$' Hide all subdirectories in this Dired buffer, leaving only their header lines (`dired-hide-all'). Or, if any subdirectory is currently hidden, make all subdirectories visible again. You can use this command to get an overview in very deep directory trees or to move quickly to subdirectories far away. Ordinary Dired commands never consider files inside a hidden subdirectory. For example, the commands to operate on marked files ignore files in hidden directories even if they are marked. Thus you can use hiding to temporarily exclude subdirectories from operations without having to remove the markers. The subdirectory hiding commands toggle; that is, they hide what was visible, and show what was hidden. File: emacs, Node: Dired Updating, Next: Dired and Find, Prev: Hiding Subdirectories, Up: Dired Updating the Dired Buffer ========================= This section describes commands to update the Dired buffer to reflect outside (non-Dired) changes in the directories and files, and to delete part of the Dired buffer. Update the entire contents of the Dired buffer (`revert-buffer'). Update the specified files (`dired-do-redisplay'). Delete the specified *file lines*--not the files, just the lines (`dired-do-kill-lines'). Toggle between sorting by file name and sorting by date/time (`dired-sort-toggle-or-edit'). `C-u s SWITCHES RET' Refresh the Dired buffer using SWITCHES as `dired-listing-switches'. Type `g' (`revert-buffer') to update the contents of the Dired buffer, based on changes in the files and directories listed. This preserves all marks except for those on files that have vanished. Hidden subdirectories are updated but remain hidden. To update only some of the files, type `l' (`dired-do-redisplay'). This command applies to the next N files, or to the marked files if any, or to the current file. Updating them means reading their current status from the file system and changing the buffer to reflect it properly. If you use `l' on a subdirectory header line, it updates the contents of the corresponding subdirectory. To delete the specified *file lines*--not the files, just the lines--type `k' (`dired-do-kill-lines'). This command applies to the next N files, or to the marked files if any, or to the current file. If you kill the line for a file that is a directory, the directory's contents are also deleted from the buffer. Typing `C-u k' on the header line for a subdirectory is another way to delete a subdirectory from the Dired buffer. The `g' command brings back any individual lines that you have killed in this way, but not subdirectories--you must use `i' to reinsert each subdirectory. The files in a Dired buffers are normally in listed alphabetical order by file names. Alternatively Dired can sort them by date/time. The Dired command `s' (`dired-sort-toggle-or-edit') switches between these two sorting modes. The mode line in a Dired buffer indicates which way it is currently sorted--by name, or by date. `C-u s SWITCHES RET' lets you specify a new value for `dired-listing-switches'. File: emacs, Node: Dired and Find, Prev: Dired Updating, Up: Dired Dired and `find' ================ You can select a set of files for display in a Dired buffer more flexibly by using the `find' utility to choose the files. To search for files with names matching a wildcard pattern use `M-x find-name-dired'. It reads arguments DIRECTORY and PATTERN, and chooses all the files in DIRECTORY or its subdirectories whose individual names match PATTERN. The files thus chosen are displayed in a Dired buffer in which the ordinary Dired commands are available. If you want to test the contents of files, rather than their names, use `M-x find-grep-dired'. This command reads two minibuffer arguments, DIRECTORY and REGEXP; it chooses all the files in DIRECTORY or its subdirectories that contain a match for REGEXP. It works by running the programs `find' and `grep'. The most general command in this series is `M-x find-dired', which lets you specify any condition that `find' can test. It takes two minibuffer arguments, DIRECTORY and FIND-ARGS; it runs `find' in DIRECTORY, passing FIND-ARGS to tell `find' what condition to test. To use this command, you need to know how to use `find'. File: emacs, Node: Calendar/Diary, Next: GNUS, Prev: Dired, Up: Top The Calendar 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. To exit the calendar, type `q'. `Mouse-3' in the calendar brings up a menu of commonly used calendar features. *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. * Counting Days:: How many days are there between two dates? * General Calendar:: Exiting or recomputing the calendar. * 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. * Appointments:: Reminders when it's time to do something. * Daylight Savings:: How to specify when daylight savings time is active. File: emacs, Node: Calendar Motion, Next: Scroll Calendar, 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, 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: emacs, Node: Calendar Unit Motion, Next: Move to Beginning or End, Up: Calendar Motion Motion by Standard Lengths of Time ---------------------------------- 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-forward-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: emacs, 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: emacs, Node: Specified Dates, Prev: Move to Beginning or End, Up: Calendar Motion Specified 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'). 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: emacs, Node: Scroll Calendar, Next: Counting Days, Prev: Calendar Motion, Up: Calendar/Diary Scrolling in the Calendar ========================= 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' `NEXT' Scroll calendar three months forward (`scroll-calendar-left-three-months'). `M-v' `PRIOR' 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 NEXT and PRIOR are equivalent to `C-v' and `M-v', just as they are in other modes. File: emacs, Node: Counting Days, Next: General Calendar, Prev: Scroll Calendar, Up: Calendar/Diary Counting Days ============= `M-=' Display the number of days in the current region (`calendar-count-days-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. File: emacs, Node: General Calendar, Next: Holidays, Prev: Counting Days, Up: Calendar/Diary Miscellaneous Calendar Commands =============================== `p d' Display day-in-year (`calendar-print-day-of-year'). `C-c C-l' Regenerate the calendar window (`redraw-calendar'). `SPC' Scroll the next window (`scroll-other-window'). Exit from calendar (`exit-calendar'). To print the number of days 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. The number of days elapsed includes the selected date. The number of days remaining does not include that date. 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 and returns the window display to what it was when you entered the calendar. File: emacs, Node: Holidays, Next: Sunrise/Sunset, Prev: General Calendar, Up: Calendar/Diary Holidays ======== The Emacs calendar knows about all major and many minor holidays, and can display them. Display holidays for the selected date (`calendar-cursor-holidays'). `Mouse-2 Holidays' Display any diary entries for the date you click on. Mark holidays in the calendar window (`mark-calendar-holidays'). Unmark calendar window (`calendar-unmark'). 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. 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 `Mouse-2' 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 SPC 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 American holidays and the major Christian, Jewish, and Islamic holidays; also the solstices and equinoxes. 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 American law mandates that daylight savings time begins on the first Sunday in April. In an American locale, Emacs always uses this definition, even though it is wrong for some prior years. File: emacs, 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. Display times of sunrise and sunset for the selected date (`calendar-sunrise-sunset'). `Mouse-2 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 `Mouse-2' 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. File: emacs, 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." 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: emacs, Node: Other Calendars, Next: Diary, 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. File: emacs, Node: Calendar Systems, Next: To Other Calendar, 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. File: emacs, 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: `Mouse-2 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 m' Display Mayan date for selected day (`calendar-print-mayan-date'). If you are using X windows, the easiest way to translate a date into other calendars is to click on it with `Mouse-2', 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: emacs, 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'). 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.