misc-utils/cal.1

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  35 .\"     @(#)cal.1       8.1 (Berkeley) 6/6/93
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  37 .TH CAL 1 "January 2018" "util-linux" "User Commands"
  38 .SH NAME
  39 cal \- display a calendar
  40 .SH SYNOPSIS
  41 .B cal
  42 [options]
  43 .RI [[[ day ] " month" ] " year" ]
  44 .br
  45 .B cal
  46 [options]
  47 .RI [ "timestamp" | "monthname" ]
  48 .SH DESCRIPTION
  49 .B cal
  50 displays a simple calendar.  If no arguments are specified, the current
  51 month is displayed.
  52 .sp
  53 The \fImonth\fR may be specified as a number (1-12), as a month name or as an
  54 abbreviated month name according to the current locales.
  55 .sp
  56 Two different calendar systems are used, Gregorian and Julian.  These are
  57 nearly identical systems with Gregorian making a small adjustment to the
  58 frequency of leap years; this facilitates improved synchronization with solar
  59 events like the equinoxes.  The Gregorian calendar reform was introduced in
  60 1582, but its adoption continued up to 1923.  By default
  61 .B cal
  62 uses the adoption date of 3 Sept 1752.  From that date forward the Gregorian
  63 calendar is displayed; previous dates use the Julian calendar system.  11 days
  64 were removed at the time of adoption to bring the calendar in sync with solar
  65 events.  So Sept 1752 has a mix of Julian and Gregorian dates by which the 2nd
  66 is followed by the 14th (the 3rd through the 13th are absent).
  67 .sp
  68 Optionally, either the proleptic Gregorian calendar or the Julian calendar may
  69 be used exclusively.
  70 .RB See\  \-\-reform\  below.
  71 .SH OPTIONS
  72 .TP
  73 \fB\-1\fR, \fB\-\-one\fR
  74 Display single month output.
  75 (This is the default.)
  76 .TP
  77 \fB\-3\fR, \fB\-\-three\fR
  78 Display three months spanning the date.
  79 .TP
  80 \fB\-n , \-\-months\fR \fInumber\fR
  81 Display \fInumber\fR of months, starting from the month containing the date.
  82 .TP
  83 \fB\-S, \fB\-\-span\fR
  84 Display months spanning the date.
  85 .TP
  86 \fB\-s\fR, \fB\-\-sunday\fR
  87 Display Sunday as the first day of the week.
  88 .TP
  89 \fB\-m\fR, \fB\-\-monday\fR
  90 Display Monday as the first day of the week.
  91 .TP
  92 \fB\-v\fR, \fB\-\-vertical\fR
  93 Display using a vertical layout (aka ncal mode).
  94 .TP
  95 .B \-\-iso
  96 Display the proleptic Gregorian calendar exclusively.  This option does not affect
  97 week numbers and the first day of the week.
  98 .RB See\  \-\-reform\  below.
  99 .TP
 100 \fB\-j\fR, \fB\-\-julian\fR
 101 Use day-of-year numbering for all calendars.  These are also called ordinal
 102 days.  Ordinal days range from 1 to 366.  This option does not switch from the
 103 Gregorian to the Julian calendar system, that is controlled by the
 104 .BR \-\-reform\  option.
 105 .sp
 106 Sometimes Gregorian calendars using ordinal dates are referred to as Julian
 107 calendars.  This can be confusing due to the many date related conventions that
 108 use Julian in their name: (ordinal) julian date, julian (calendar) date,
 109 (astronomical) julian date, (modified) julian date, and more.  This option is
 110 named julian, because ordinal days are identified as julian by the POSIX
 111 standard.  However, be aware that
 112 .B cal
 113 also uses the Julian calendar system.
 114 .RB See\  DESCRIPTION\  above.
 115 .TP
 116 .BI \-\-reform\  val
 117 This option sets the adoption date of the Gregorian calendar reform.  Calendar
 118 dates previous to reform use the Julian calendar system.  Calendar dates
 119 after reform use the Gregorian calendar system.  The argument
 120 .I val
 121 can be:
 122 .RS
 123 .IP \(bu 2
 124 .I 1752
 125 - sets 3 September 1752 as the reform date (default).
 126 This is when the Gregorian calendar reform was adopted by the British Empire.
 127 .IP \(bu 2
 128 .I gregorian
 129 - display Gregorian calendars exclusively.  This special placeholder sets the
 130 reform date below the smallest year that
 131 .B cal
 132 can use; meaning all calendar output uses the Gregorian calendar system.  This
 133 is called the proleptic Gregorian calendar, because dates prior to the calendar
 134 system's creation use extrapolated values.
 135 .IP \(bu 2
 136 .I iso
 137 - alias of
 138 .IR gregorian .
 139 The ISO 8601 standard for the representation of dates and times in information
 140 interchange requires using the proleptic Gregorian calendar.
 141 .IP \(bu 2
 142 .I julian
 143 - display Julian calendars exclusively.  This special placeholder sets the reform date above the largest year that
 144 .B cal
 145 can use; meaning all
 146 calendar output uses the Julian calendar system.
 147 .PP
 148 .RB See\  \%DESCRIPTION\  above.
 149 .RE
 150 .TP
 151 \fB\-y\fR, \fB\-\-year\fR
 152 Display a calendar for the whole year.
 153 .TP
 154 \fB\-Y, \fB\-\-twelve\fR
 155 Display a calendar for the next twelve months.
 156 .TP
 157 \fB\-w\fR, \fB\-\-week\fR[=\fInumber\fR]
 158 Display week numbers in the calendar (US or ISO-8601).  See NOTES section
 159 for more details.
 160 .TP
 161 \fB\-\-color\fR[=\fIwhen\fR]
 162 Colorize the output.  The optional argument \fIwhen\fP
 163 can be \fBauto\fR, \fBnever\fR or \fBalways\fR.  If the \fIwhen\fR argument is omitted,
 164 it defaults to \fBauto\fR.  The colors can be disabled; for the current built-in default
 165 see the \fB\-\-help\fR output.  See also the \fBCOLORS\fR section.
 166 .TP
 167 \fB\-V\fR, \fB\-\-version\fR
 168 Display version information and exit.
 169 .TP
 170 \fB\-h\fR, \fB\-\-help\fR
 171 Display help text and exit.
 172 .SH PARAMETERS
 173 .TP
 174 \fBSingle digits-only parameter (e.g., 'cal 2020')\fR
 175 Specifies the \fIyear\fR to be displayed; note the year must be fully specified:
 176 .B "cal 89"
 177 will not display a calendar for 1989.
 178 .TP
 179 \fBSingle string parameter (e.g., 'cal tomorrow' or 'cal August')\fR
 180 Specifies \fItimestamp\fR or a \fImonth name\fR (or abbreviated name) according to the current
 181 locales.
 182 .sp
 183 The special placeholders are accepted when parsing timestamp, "now" may be used
 184 to refer to the current time, "today", "yesterday", "tomorrow" refer to of the
 185 current day, the day before or the next day, respectively.
 186 .sp
 187 The relative date specifications are also accepted, in this case "+" is
 188 evaluated to the current time plus the specified time span. Correspondingly, a
 189 time span that is prefixed with "-" is evaluated to the current time minus the
 190 specified time span, for example '+2days'. Instead of prefixing the time span
 191 with "+" or "-", it may also be suffixed with a space and the word "left" or
 192 "ago" (for example '1 week ago').
 193 .TP
 194 \fBTwo parameters (e.g., 'cal 11 2020')\fR
 195 Denote the \fImonth\fR (1 - 12) and \fIyear\fR.
 196 .TP
 197 \fBThree parameters (e.g., 'cal 25 11 2020')\fR
 198 Denote the \fIday\fR (1-31), \fImonth and \fIyear\fR, and the day will be
 199 highlighted if the calendar is displayed on a terminal.  If no parameters are
 200 specified, the current month's calendar is displayed.
 201 .SH NOTES
 202 A year starts on January 1.  The first day of the week is determined by the
 203 locale or the
 204 .BR \-\-sunday \ and \ \-\-monday \ options.
 205 .PP
 206 The week numbering depends on the choice of the first day of the week.  If it
 207 is Sunday then the customary North American numbering is used, where 1 January
 208 is in week number 1.  If it is Monday (\fB\-m\fR) then the ISO 8601 standard week
 209 numbering is used, where the first Thursday is in week number 1.
 210 .SH COLORS
 211 Implicit coloring can be disabled as follows:
 212 .RS
 213
 214 .br
 215 .B touch /etc/terminal-colors.d/cal.disable
 216 .br
 217
 218 .RE
 219 See
 220 .BR terminal-colors.d (5)
 221 for more details about colorization configuration.
 222 .SH HISTORY
 223 A cal command appeared in Version 6 AT&T UNIX.
 224 .SH BUGS
 225 .PP
 226 The default
 227 .B cal
 228 output uses 3 September 1752 as the Gregorian calendar reform date.  The
 229 historical reform  dates for the other locales, including its introduction in
 230 October 1582, are not implemented.
 231 .PP
 232 Alternative calendars, such as the Umm al-Qura, the Solar Hijri, the Ge'ez,
 233 or the lunisolar Hindu, are not supported.
 234 .SH AVAILABILITY
 235 The cal command is part of the util-linux package and is available from
 236 https://www.kernel.org/pub/linux/utils/util-linux/.