xref: /freebsd/usr.bin/calendar/calendar.1 (revision c90590dd92e3e2c30cc24f8042c77d8d2494e228)
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28.\"     @(#)calendar.1  8.1 (Berkeley) 6/29/93
29.\" $FreeBSD$
30.\"
31.Dd October 25, 2020
32.Dt CALENDAR 1
33.Os
34.Sh NAME
35.Nm calendar
36.Nd reminder service
37.Sh SYNOPSIS
38.Nm
39.Op Fl A Ar num
40.Op Fl a
41.Op Fl B Ar num
42.Op Fl D Ar moon|sun
43.Op Fl d
44.Op Fl F Ar friday
45.Op Fl f Ar calendarfile
46.Op Fl l Ar longitude
47.Oo
48.Bk -words
49.Fl t Ar dd Ns
50.Sm off
51.Op . Ar mm Op . Ar year
52.Sm on
53.Ek
54.Oc
55.Op Fl U Ar UTC-offset
56.Op Fl W Ar num
57.Sh DESCRIPTION
58The
59.Nm
60utility checks the current directory for a file named
61.Pa calendar
62and displays lines that fall into the specified date range.
63On the day before a weekend (normally Friday), events for the next
64three days are displayed.
65.Pp
66The following options are available:
67.Bl -tag -width Ds
68.It Fl A Ar num
69Print lines from today and the next
70.Ar num
71days (forward, future).
72.It Fl a
73Process the ``calendar'' files for users found in
74.Pa /etc/passwd
75and mail the results
76to them.
77This can result in multiple messages for specific files, since
78.Pa /etc/passwd
79does not require home directories to be unique.
80In particular, by default
81.Ar root ,
82.Ar toor
83and
84.Ar daemon
85share the same home directory.
86If this directory contains calendar information,
87.Nm
88will process the file three times.
89.Pp
90This option requires super-user privileges.
91.It Fl B Ar num
92Print lines from today and the previous
93.Ar num
94days (backward, past).
95.It Fl D Ar moon|sun
96Print UTC offset, longitude and moon or sun information.
97.It Fl d
98Debug option: print current date information.
99.It Fl F Ar friday
100Specify which day of the week is ``Friday'' (the day before the
101weekend begins).
102Default is 5.
103.It Fl f Pa calendarfile
104Use
105.Pa calendarfile
106as the default calendar file.
107.It Fl l Ar longitude
108Perform lunar and solar calculations from this longitude.
109If neither longitude nor UTC offset is specified, the calculations will
110be based on the difference between UTC time and localtime.
111If both are specified, UTC offset overrides longitude.
112.It Xo Fl t
113.Sm off
114.Ar dd
115.Op . Ar mm Op . Ar year
116.Sm on
117.Xc
118For test purposes only: set date directly to argument values.
119.It Fl U Ar UTC-offset
120Perform lunar and solar calculations from this UTC offset.
121If neither UTC offset nor longitude is specified, the calculations
122will be based on the difference between UTC time and localtime.
123If both are specified, UTC offset overrides longitude.
124.It Fl W Ar num
125Print lines from today and the next
126.Ar num
127days (forward, future).
128Ignore weekends when calculating the number of days.
129.El
130.Sh FILE FORMAT
131To handle calendars in your national code table you can specify
132.Dq LANG=<locale_name>
133in the calendar file as early as possible.
134.Pp
135To handle the local name of sequences, you can specify them as:
136.Dq SEQUENCE=<first> <second> <third> <fourth> <fifth> <last>
137in the calendar file as early as possible.
138.Pp
139The names of the following special days are recognized:
140.Bl -tag -width 123456789012345 -compact
141.It Easter
142Catholic Easter.
143.It Paskha
144Orthodox Easter.
145.It NewMoon
146The lunar New Moon.
147.It FullMoon
148The lunar Full Moon.
149.It MarEquinox
150The solar equinox in March.
151.It JunSolstice
152The solar solstice in June.
153.It SepEquinox
154The solar equinox in September.
155.It DecSolstice
156The solar solstice in December.
157.It ChineseNewYear
158The first day of the Chinese year.
159.El
160These names may be reassigned to their local names via an assignment
161like
162.Dq Easter=Pasen
163in the calendar file.
164.Pp
165Other lines should begin with a month and day.
166They may be entered in almost any format, either numeric or as character
167strings.
168If the proper locale is set, national month and weekday
169names can be used.
170A single asterisk (``*'') matches every month.
171A day without a month matches that day of every week.
172A month without a day matches the first of that month.
173Two numbers default to the month followed by the day.
174Lines with leading tabs default to the last entered date, allowing
175multiple line specifications for a single date.
176.Pp
177The names of the recognized special days may be followed by a
178positive or negative integer, like:
179.Dq Easter+3
180or
181.Dq Paskha-4 .
182.Pp
183Weekdays may be followed by ``-4'' ...\& ``+5'' (aliases for
184last, first, second, third, fourth) for moving events like
185``the last Monday in April''.
186.Pp
187By convention, dates followed by an asterisk are not fixed, i.e., change
188from year to year.
189.Pp
190Day descriptions start after the first <tab> character in the line;
191if the line does not contain a <tab> character, it is not displayed.
192If the first character in the line is a <tab> character, it is treated as
193a continuation of the previous line.
194.Pp
195The
196.Nm
197file is preprocessed by a limited subset of
198.Xr cpp 1
199internally, allowing the inclusion of shared files such as
200lists of company holidays or meetings.
201This limited subset consists of \fB#include #ifndef #endif\fR and \fB#define\fR.
202If the shared file is not referenced by a full pathname,
203.Nm
204searches in the current (or home) directory first, and then in the
205directory
206.Pa /usr/share/calendar .
207Empty lines and lines protected by the C commenting syntax
208.Pq Li /* ... */
209are ignored.
210.Pp
211Some possible calendar entries (<tab> characters highlighted by
212\fB\et\fR sequence)
213.Bd -unfilled -offset indent
214LANG=C
215Easter=Ostern
216
217#include <calendar.usholiday>
218#include <calendar.birthday>
219
2206/15\fB\et\fRJune 15 (if ambiguous, will default to month/day).
221Jun. 15\fB\et\fRJune 15.
22215 June\fB\et\fRJune 15.
223Thursday\fB\et\fREvery Thursday.
224June\fB\et\fREvery June 1st.
22515 *\fB\et\fR15th of every month.
2262010/4/15\fB\et\fR15 April 2010
227
228May Sun+2\fB\et\fRsecond Sunday in May (Muttertag)
22904/SunLast\fB\et\fRlast Sunday in April,
230\fB\et\fRsummer time in Europe
231Easter\fB\et\fREaster
232Ostern-2\fB\et\fRGood Friday (2 days before Easter)
233Paskha\fB\et\fROrthodox Easter
234
235.Ed
236.Sh FILES
237.Bl -tag -width calendar.christian -compact
238.It Pa calendar
239file in current directory.
240.It Pa ~/.calendar
241.Pa calendar
242HOME directory.
243A chdir is done into this directory if it exists.
244.It Pa ~/.calendar/calendar
245calendar file to use if no calendar file exists in the current directory.
246.It Pa ~/.calendar/nomail
247do not send mail if this file exists.
248.It Pa /usr/share/calendar
249system wide location of calendar files provided as part of the base system.
250.It Pa /usr/local/share/calendar
251system wide location for calendar files provided by a port or package.
252.El
253.Pp
254The order of precedence in searches for a calendar file is:
255current directory, ~/.calendar, /usr/local/share/calendar, /usr/share/calendar.
256Files of similar names are ignored in lower precedence locations.
257.Pp
258The following default calendar files are provided by the
259deskutils/calendar-data port.
260.Pp
261.Bl -tag -width calendar.southafrica -compact
262.It Pa calendar.all
263File which includes all the default files.
264.It Pa calendar.australia
265Calendar of events in Australia.
266.It Pa calendar.birthday
267Births and deaths of famous (and not-so-famous) people.
268.It Pa calendar.christian
269Christian holidays.
270This calendar should be updated yearly by the local system administrator
271so that roving holidays are set correctly for the current year.
272.It Pa calendar.computer
273Days of special significance to computer people.
274.It Pa calendar.croatian
275Calendar of events in Croatia.
276.It Pa calendar.dutch
277Calendar of events in the Netherlands.
278.It Pa calendar.freebsd
279Birthdays of
280.Fx
281committers.
282.It Pa calendar.french
283Calendar of events in France.
284.It Pa calendar.german
285Calendar of events in Germany.
286.It Pa calendar.history
287Everything else, mostly U.S.\& historical events.
288.It Pa calendar.holiday
289Other holidays, including the not-well-known, obscure, and
290.Em really
291obscure.
292.It Pa calendar.judaic
293Jewish holidays.
294The entries for this calendar have been obtained from the
295deskutils/hebcal port.
296.It Pa calendar.music
297Musical events, births, and deaths.
298Strongly oriented toward rock 'n' roll.
299.It Pa calendar.newzealand
300Calendar of events in New Zealand.
301.It Pa calendar.russian
302Russian calendar.
303.It Pa calendar.southafrica
304Calendar of events in South Africa.
305.It Pa calendar.usholiday
306U.S.\& holidays.
307This calendar should be updated yearly by the local system administrator
308so that roving holidays are set correctly for the current year.
309.It Pa calendar.world
310Includes all calendar files except for national files.
311.El
312.Sh COMPATIBILITY
313The
314.Nm
315program previously selected lines which had the correct date anywhere
316in the line.
317This is no longer true, the date is only recognized when it occurs
318at the beginning of a line.
319.Sh SEE ALSO
320.Xr at 1 ,
321.Xr mail 1 ,
322.Xr cron 8
323.Sh HISTORY
324A
325.Nm
326command appeared in
327.At v7 .
328.Sh NOTES
329Chinese New Year is calculated at 120 degrees east of Greenwich,
330which roughly corresponds with the east coast of China.
331For people west of China, this might result that the start of Chinese
332New Year and the day of the related new moon might differ.
333.Pp
334The phases of the moon and the longitude of the sun are calculated
335against the local position which corresponds with 30 degrees times
336the time-difference towards Greenwich.
337.Pp
338The new and full moons are happening on the day indicated: They
339might happen in the time period in the early night or in the late
340evening.
341It does not indicate that they are starting in the night on that date.
342.Pp
343Because of minor differences between the output of the formulas
344used and other sources on the Internet, Druids and Werewolves should
345double-check the start and end time of solar and lunar events.
346.Sh BUGS
347The
348.Nm
349internal cpp does not correctly do #ifndef and will discard the rest
350of the file if a #ifndef is triggered.
351It also has a maximum of 50 include file and/or 100 #defines
352and only recognises #include, #define and
353#ifndef.
354.Pp
355There is no possibility to properly specify the local position
356needed for solar and lunar calculations.
357