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 .B \-\-iso
  93 Display the proleptic Gregorian calendar exclusively.
  94 .RB See\  \-\-reform\  below.
  95 .TP
  96 \fB\-j\fR, \fB\-\-julian\fR
  97 Use day-of-year numbering for all calendars.  These are also called ordinal
  98 days.  Ordinal days range from 1 to 366.  This option does not switch from the
  99 Gregorian to the Julian calendar system, that is controlled by the
 100 .BR \-\-reform\  option.
 101 .sp
 102 Sometimes Gregorian calendars using ordinal dates are referred to as Julian
 103 calendars.  This can be confusing due to the many date related conventions that
 104 use Julian in their name: (ordinal) julian date, julian (calendar) date,
 105 (astronomical) julian date, (modified) julian date, and more.  This option is
 106 named julian, because ordinal days are identified as julian by the POSIX
 107 standard.  However, be aware that
 108 .B cal
 109 also uses the Julian calendar system.
 110 .RB See\  DESCRIPTION\  above.
 111 .TP
 112 .BI \-\-reform\  val
 113 This option sets the adoption date of the Gregorian calendar reform.  Calendar
 114 dates previous to reform use the Julian calendar system.  Calendar dates
 115 after reform use the Gregorian calendar system.  The argument
 116 .I val
 117 can be:
 118 .RS
 119 .IP \(bu 2
 120 .I 1752
 121 - sets 3 September 1752 as the reform date (default).
 122 This is when the Gregorian calendar reform was adopted by the British Empire.
 123 .IP \(bu 2
 124 .I gregorian
 125 - display Gregorian calendars exclusively.  This special placeholder sets the
 126 reform date below the smallest year that
 127 .B cal
 128 can use; meaning all calendar output uses the Gregorian calendar system.  This
 129 is called the proleptic Gregorian calendar, because dates prior to the calendar
 130 system's creation use extrapolated values.
 131 .IP \(bu 2
 132 .I iso
 133 - alias of
 134 .IR gregorian .
 135 The ISO 8601 standard for the representation of dates and times in information
 136 interchange requires using the proleptic Gregorian calendar.
 137 .IP \(bu 2
 138 .I julian
 139 - display Julian calendars exclusively.  This special placeholder sets the reform date above the largest year that
 140 .B cal
 141 can use; meaning all
 142 calendar output uses the Julian calendar system.
 143 .PP
 144 .RB See\  \%DESCRIPTION\  above.
 145 .RE
 146 .TP
 147 \fB\-y\fR, \fB\-\-year\fR
 148 Display a calendar for the whole year.
 149 .TP
 150 \fB\-Y, \fB\-\-twelve\fR
 151 Display a calendar for the next twelve months.
 152 .TP
 153 \fB\-w\fR, \fB\-\-week\fR[=\fInumber\fR]
 154 Display week numbers in the calendar (US or ISO-8601).
 155 .TP
 156 \fB\-\-color\fR[=\fIwhen\fR]
 157 Colorize the output.  The optional argument \fIwhen\fP
 158 can be \fBauto\fR, \fBnever\fR or \fBalways\fR.  If the \fIwhen\fR argument is omitted,
 159 it defaults to \fBauto\fR.  The colors can be disabled; for the current built-in default
 160 see the \fB\-\-help\fR output.  See also the \fBCOLORS\fR section.
 161 .TP
 162 \fB\-V\fR, \fB\-\-version\fR
 163 Display version information and exit.
 164 .TP
 165 \fB\-h\fR, \fB\-\-help\fR
 166 Display help text and exit.
 167 .SH PARAMETERS
 168 .TP
 169 \fBSingle digits-only parameter (e.g. 'cal 2020')\fR
 170 Specifies the \fIyear\fR to be displayed; note the year must be fully specified:
 171 .B "cal 89"
 172 will not display a calendar for 1989.
 173 .TP
 174 \fBSingle string parameter (e.g. 'cal tomorrow' or 'cal August')\fR
 175 Specifies \fItimestamp\fR or a \fImonth name\fR (or abbreviated name) according to the current
 176 locales.
 177 .sp
 178 The special placeholders are accepted when parsing timestamp, "now" may be used
 179 to refer to the current time, "today", "yesterday", "tomorrow" refer to of the
 180 current day, the day before or the next day, respectively.
 181 .sp
 182 The relative date specifications are also accepted, in this case "+" is
 183 evaluated to the current time plus the specified time span. Correspondingly, a
 184 time span that is prefixed with "-" is evaluated to the current time minus the
 185 specified time span, for example '+2days'. Instead of prefixing the time span
 186 with "+" or "-", it may also be suffixed with a space and the word "left" or
 187 "ago" (for example '1 week ago').
 188 .TP
 189 \fBTwo parameters (e.g. 'cal 11 2020')\fR
 190 Denote the \fImonth\fR (1 - 12) and \fIyear\fR.
 191 .TP
 192 \fBThree parameters (e.g. 'cal 25 11 2020')\fR
 193 Denote the \fIday\fR (1-31), \fImonth and \fIyear\fR, and the day will be
 194 highlighted if the calendar is displayed on a terminal.  If no parameters are
 195 specified, the current month's calendar is displayed.
 196 .SH NOTES
 197 A year starts on January 1.  The first day of the week is determined by the
 198 locale or the
 199 .BR \-\-sunday \ and \ \-\-monday \ options.
 200 .PP
 201 The week numbering depends on the choice of the first day of the week.  If it
 202 is Sunday then the customary North American numbering is used, where 1 January
 203 is in week number 1.  If it is Monday then the ISO 8601 standard week numbering
 204 is used, where the first Thursday is in week number 1.
 205 .SH COLORS
 206 Implicit coloring can be disabled as follows:
 207 .RS
 208
 209 .br
 210 .B touch /etc/terminal-colors.d/cal.disable
 211 .br
 212
 213 .RE
 214 See
 215 .BR terminal-colors.d (5)
 216 for more details about colorization configuration.
 217 .SH BUGS
 218 .PP
 219 The default
 220 .B cal
 221 output uses 3 September 1752 as the Gregorian calendar reform date.  The
 222 historical reform  dates for the other locales, including its introduction in
 223 October 1582, are not implemented.
 224 .PP
 225 Alternative calendars, such as the Umm al-Qura, the Solar Hijri, the Ge'ez,
 226 or the lunisolar Hindu, are not supported.
 227 .SH HISTORY
 228 A cal command appeared in Version 6 AT&T UNIX.
 229 .SH AVAILABILITY
 230 The cal command is part of the util-linux package and is available from
 231 https://www.kernel.org/pub/linux/utils/util-linux/.