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CAL(1)                           User Commands                          CAL(1)
NAME
       cal - display a calendar
SYNOPSIS
       cal [options] [[[day] month] year]
       cal [options] [timestamp|monthname]
DESCRIPTION
       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 synchroniza-
       tion 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 cal-
       endar may be used exclusively.  See --reform below.
OPTIONS
       -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.
       --iso  Display    the   proleptic   Gregorian   calendar   exclusively.
              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: (ordi-
              nal) 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 calen-
              dar system.  Calendar dates after reform use the Gregorian  cal-
              endar system.  The argument val can be:
              o 1752  -  sets  3  September 1752 as the reform date (default).
                This is when the Gregorian calendar reform was adopted by  the
                British Empire.
              o 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  Gre-
                gorian  calendar, because dates prior to the calendar system's
                creation use extrapolated values.
              o iso - alias of gregorian.  The ISO 8601 standard for the  rep-
                resentation  of  dates  and  times  in information interchange
                requires using the proleptic Gregorian calendar.
              o 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  cal-
                endar 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).
       --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
       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", "yes-
              terday", "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 high-
              lighted if the calendar is  displayed  on  a  terminal.   If  no
              parameters  are  specified, the current month's calendar is dis-
              played.
NOTES
       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 then the ISO 8601
       standard week numbering is used, where the first Thursday  is  in  week
       number 1.
COLORS
       Implicit coloring can be disabled as follows:
              touch /etc/terminal-colors.d/cal.disable
       See terminal-colors.d(5) for more details about colorization configura-
       tion.
BUGS
       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.
HISTORY
       A cal command appeared in Version 6 AT&T UNIX.
AVAILABILITY
       The cal command is part of the util-linux package and is available from
       https://www.kernel.org/pub/linux/utils/util-linux/.
util-linux                       January 2018                           CAL(1)