cal — display a calendar
cal [options] [ [ [day]
month ] year ]
cal [options] [ timestamp |
monthname ]
cal displays a simple calendar. If no arguments are specified, the current month is displayed.
The month may be
specified as a number (1-12), as a month name or as an
abbreviated month name according to the current locales.
Two different calendar systems are used, Gregorian and Julian. These are nearly identical systems with Gregorian making a small adjustment to the frequency of leap years; this facilitates improved synchronization with solar events like the equinoxes. The Gregorian calendar reform was introduced in 1582, but its adoption continued up to 1923. By default cal uses the adoption date of 3 Sept 1752. From that date forward the Gregorian calendar is displayed; previous dates use the Julian calendar system. 11 days were removed at the time of adoption to bring the calendar in sync with solar events. So Sept 1752 has a mix of Julian and Gregorian dates by which the 2nd is followed by the 14th (the 3rd through the 13th are absent).
Optionally, either the proleptic Gregorian calendar or the
Julian calendar may be used exclusively. See −−reformbelow.
−−oneDisplay single month output. (This is the default.)
−−threeDisplay three months spanning the date.
−n ,
−−months numberDisplay number of months, starting from the month containing the date.
−S, −−spanDisplay months spanning the date.
−s, −−sundayDisplay Sunday as the first day of the week.
−m, −−mondayDisplay Monday as the first day of the week.
−v, −−verticalDisplay using a vertical layout (aka ncal mode).
−−isoDisplay the proleptic Gregorian calendar
exclusively. This option does not affect week numbers
and the first day of the week. See −−reformbelow.
−j, −−julianUse day-of-year numbering for all calendars. These
are also called ordinal days. Ordinal days range from 1
to 366. This option does not switch from the Gregorian
to the Julian calendar system, that is controlled by
the −−reformoption.
Sometimes Gregorian calendars using ordinal dates
are referred to as Julian calendars. This can be
confusing due to the many date related conventions that
use Julian in their name: (ordinal) julian date, julian
(calendar) date, (astronomical) julian date, (modified)
julian date, and more. This option is named julian,
because ordinal days are identified as julian by the
POSIX standard. However, be aware that cal also uses the
Julian calendar system. See DESCRIPTIONabove.
−−reform valThis option sets the adoption date of the Gregorian calendar reform. Calendar dates previous to reform use the Julian calendar system. Calendar dates after reform use the Gregorian calendar system. The argument val can be:
1752- sets 3 September 1752 as the reform date (default). This is when the Gregorian calendar reform was adopted by the British Empire.gregorian - display Gregorian calendars exclusively. This special placeholder sets the reform date below the smallest year that cal can use; meaning all calendar output uses the Gregorian calendar system. This is called the proleptic Gregorian calendar, because dates prior to the calendar system's creation use extrapolated values.
iso - alias of gregorian. The ISO 8601 standard for the representation of dates and times in information interchange requires using the proleptic Gregorian calendar.
julian - display Julian calendars exclusively. This special placeholder sets the reform date above the largest year that cal can use; meaning all calendar output uses the Julian calendar system.
See
DESCRIPTIONabove.
−y, −−yearDisplay a calendar for the whole year.
−Y, −−twelveDisplay a calendar for the next twelve months.
−w, −−week[=number]Display week numbers in the calendar (US or ISO-8601). See NOTES section for more details.
−−color[=when]Colorize the output. The optional argument
when can
be auto,
never or
always.
If the when argument is
omitted, it defaults to auto. The colors can
be disabled; for the current built-in default see the
−−help output.
See also the COLORS
section.
−V, −−versionDisplay version information and exit.
−h, −−helpDisplay help text and exit.
Specifies the year to be displayed;
note the year must be fully specified: cal 89 will not display a
calendar for 1989.
Specifies timestamp or a
month name (or
abbreviated name) according to the current locales.
The special placeholders are accepted when parsing timestamp, "now" may be used to refer to the current time, "today", "yesterday", "tomorrow" refer to of the current day, the day before or the next day, respectively.
The relative date specifications are also accepted, in this case "+" is evaluated to the current time plus the specified time span. Correspondingly, a time span that is prefixed with "-" is evaluated to the current time minus the specified time span, for example '+2days'. Instead of prefixing the time span with "+" or "-", it may also be suffixed with a space and the word "left" or "ago" (for example '1 week ago').
Denote the month (1 - 12) and
year.
Denote the day (1-31), month and year, and the day will be
highlighted if the calendar is displayed on a terminal.
If no parameters are specified, the current month's
calendar is displayed.
A year starts on January 1. The first day of the week is
determined by the locale or the −−sundayand−−mondayoptions.
The week numbering depends on the choice of the first day
of the week. If it is Sunday then the customary North
American numbering is used, where 1 January is in week number
1. If it is Monday (−m)
then the ISO 8601 standard week numbering is used, where the
first Thursday is in week number 1.
Implicit coloring can be disabled as follows:
touch /etc/terminal-colors.d/cal.disable
See terminal-colors.d(5) for more details about colorization configuration.
The default cal output uses 3 September 1752 as the Gregorian calendar reform date. The historical reform dates for the other locales, including its introduction in October 1582, are not implemented.
Alternative calendars, such as the Umm al-Qura, the Solar Hijri, the Ge'ez, or the lunisolar Hindu, are not supported.
The cal command is part of the util-linux package and is available from https://www.kernel.org/pub/linux/utils/util-linux/.
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Copyright (c) 1989, 1990, 1993 The Regents of the University of California. All rights reserved. This code is derived from software contributed to Berkeley by Kim Letkeman. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed by the University of California, Berkeley and its contributors. 4. Neither the name of the University nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. (#)cal.1 8.1 (Berkeley) 6/6/93 |