Linux cal man
cal(1) — Linux manual page
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | PARAMETERS | NOTES | COLORS | HISTORY | BUGS | AVAILABILITY | COLOPHON
CAL(1) User Commands CAL(1)
NAME
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cal - display a calendar
SYNOPSIS
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cal [options] [[[day] month] year]
cal [options] [timestamp|monthname]
DESCRIPTION
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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 --reform below.
OPTIONS
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-1, --one
Display single month output. (This is the default.)
-3, --three
Display three months spanning the date.
-n , --months number
Display number of months, starting from the month
containing the date.
-S, --span
Display months spanning the date.
-s, --sunday
Display Sunday as the first day of the week.
-m, --monday
Display Monday as the first day of the week.
-v, --vertical
Display using a vertical layout (aka ncal mode).
--iso Display the proleptic Gregorian calendar exclusively.
This option does not affect week numbers and the first day
of the week. See --reform below.
-j, --julian
Use 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
--reform option.
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 DESCRIPTION above.
--reform val
This 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
DESCRIPTION
above.
-y, --year
Display a calendar for the whole year.
-Y, --twelve
Display 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, --version
Display version information and exit.
-h, --help
Display help text and exit.
PARAMETERS
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Single digits-only parameter (e.g., 'cal 2020')
Specifies the year to be displayed; note the year must be
fully specified: cal 89 will not display a calendar for
1989.
Single string parameter (e.g., 'cal tomorrow' or 'cal August')
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').
Two parameters (e.g., 'cal 11 2020')
Denote the month (1 - 12) and year.
Three parameters (e.g., 'cal 25 11 2020')
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.
NOTES
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A year starts on January 1. The first day of the week is
determined by the locale or the --sunday and --monday options.
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.
COLORS
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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.
HISTORY
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A cal command appeared in Version 6 AT&T UNIX.
BUGS
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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.
AVAILABILITY
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The cal command is part of the util-linux package and is
available from
https://www.kernel.org/pub/linux/utils/util-linux/
.
COLOPHON
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This page is part of the util-linux (a random collection of Linux
utilities) project. Information about the project can be found
at ⟨
https://www.kernel.org/pub/linux/utils/util-linux/
⟩. If you
have a bug report for this manual page, send it to
util-linux@vger.kernel.org. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2020-12-18. (At that time, the date of the most recent commit
that was found in the repository was 2020-12-17.) If you
discover any rendering problems in this HTML version of the page,
or you believe there is a better or more up-to-date source for
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