xref: /freebsd/usr.bin/calendar/calendar.1 (revision 752c1d14e398faab8e6f19f99ee29df87ecb05e1)
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28.\"     @(#)calendar.1  8.1 (Berkeley) 6/29/93
29.\" $FreeBSD$
30.\"
31.Dd September 29, 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.El
249.Pp
250The following default calendar files are provided in
251.Pa /usr/share/calendar :
252.Pp
253.Bl -tag -width calendar.southafrica -compact
254.It Pa calendar.all
255File which includes all the default files.
256.It Pa calendar.australia
257Calendar of events in Australia.
258.It Pa calendar.birthday
259Births and deaths of famous (and not-so-famous) people.
260.It Pa calendar.christian
261Christian holidays.
262This calendar should be updated yearly by the local system administrator
263so that roving holidays are set correctly for the current year.
264.It Pa calendar.computer
265Days of special significance to computer people.
266.It Pa calendar.croatian
267Calendar of events in Croatia.
268.It Pa calendar.dutch
269Calendar of events in the Netherlands.
270.It Pa calendar.freebsd
271Birthdays of
272.Fx
273committers.
274.It Pa calendar.french
275Calendar of events in France.
276.It Pa calendar.german
277Calendar of events in Germany.
278.It Pa calendar.history
279Everything else, mostly U.S.\& historical events.
280.It Pa calendar.holiday
281Other holidays, including the not-well-known, obscure, and
282.Em really
283obscure.
284.It Pa calendar.judaic
285Jewish holidays.
286The entries for this calendar have been obtained from the port
287deskutils/hebcal.
288.It Pa calendar.music
289Musical events, births, and deaths.
290Strongly oriented toward rock 'n' roll.
291.It Pa calendar.newzealand
292Calendar of events in New Zealand.
293.It Pa calendar.russian
294Russian calendar.
295.It Pa calendar.southafrica
296Calendar of events in South Africa.
297.It Pa calendar.usholiday
298U.S.\& holidays.
299This calendar should be updated yearly by the local system administrator
300so that roving holidays are set correctly for the current year.
301.It Pa calendar.world
302Includes all calendar files except for national files.
303.El
304.Sh COMPATIBILITY
305The
306.Nm
307program previously selected lines which had the correct date anywhere
308in the line.
309This is no longer true, the date is only recognized when it occurs
310at the beginning of a line.
311.Sh SEE ALSO
312.Xr at 1 ,
313.Xr mail 1 ,
314.Xr cron 8
315.Sh HISTORY
316A
317.Nm
318command appeared in
319.At v7 .
320.Sh NOTES
321Chinese New Year is calculated at 120 degrees east of Greenwich,
322which roughly corresponds with the east coast of China.
323For people west of China, this might result that the start of Chinese
324New Year and the day of the related new moon might differ.
325.Pp
326The phases of the moon and the longitude of the sun are calculated
327against the local position which corresponds with 30 degrees times
328the time-difference towards Greenwich.
329.Pp
330The new and full moons are happening on the day indicated: They
331might happen in the time period in the early night or in the late
332evening.
333It does not indicate that they are starting in the night on that date.
334.Pp
335Because of minor differences between the output of the formulas
336used and other sources on the Internet, Druids and Werewolves should
337double-check the start and end time of solar and lunar events.
338.Sh BUGS
339The
340.Nm
341internal cpp does not correctly do #ifndef and will discard the rest
342of the file if a #ifndef is triggered.
343It also has a maximum of 50 include file and/or 100 #defines
344and only recognises #include, #define and
345#ifndef.
346.Pp
347There is no possibility to properly specify the local position
348needed for solar and lunar calculations.
349