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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | PARAMETERS | NOTES | COLORS | HISTORY | BUGS | SEE ALSO | REPORTING BUGS | AVAILABILITY |
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CAL(1) User Commands CAL(1)
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 --reform below.
-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(1) 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 according to the US or
ISO-8601 format. If a number is specified, the requested week
will be printed in the desired or current year. The number
may be overwritten if day and month are also specified.
See the 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.
-c, --columns=columns
Number of columns to use. auto uses as many as fit the
terminal.
-h, --help
Display help text and exit.
-V, --version
Print version and exit.
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.
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.
The output colorization is implemented by terminal-colors.d(5)
functionality. Implicit coloring can be disabled by an empty file
/etc/terminal-colors.d/cal.disable
for the cal command or for all tools by
/etc/terminal-colors.d/disable
The user-specific $XDG_CONFIG_HOME/terminal-colors.d or
$HOME/.config/terminal-colors.d overrides the global setting.
Note that the output colorization may be enabled by default, and
in this case terminal-colors.d directories do not have to exist
yet.
The logical color names supported by cal are:
today
The current day.
weeknumber
The week number requested by the --week=<number> command line
option.
weeks
The number of the week.
header
The header of a month.
workday
Days that fall within the work-week.
weekend
Days that fall outside the work-week.
For example:
echo -e 'weekend 35\ntoday 1;41\nheader yellow' >
$HOME/.config/terminal-colors.d/cal.scheme
A cal command appeared in Version 6 AT&T UNIX.
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.
terminal-colors.d(5)
For bug reports, use the issue tracker at
https://github.com/util-linux/util-linux/issues.
The cal command is part of the util-linux package which can be
downloaded from Linux Kernel Archive
<https://www.kernel.org/pub/linux/utils/util-linux/>. 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
[email protected]. This page was obtained from the
project's upstream Git repository
⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
2024-06-14. (At that time, the date of the most recent commit
that was found in the repository was 2024-06-10.) 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 the page,
or you have corrections or improvements to the information in
this COLOPHON (which is not part of the original manual page),
send a mail to [email protected]
util-linux 2.41.devel-537-e... 2024-06-13 CAL(1)
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HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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