CAL(1P) POSIX Programmer's Manual CAL(1P)PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding
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NAMEcal - print a calendar
SYNOPSIScal [[month] year ]
The cal utility shall write a calendar to standard output using the
Julian calendar for dates from January 1, 1 through September 2, 1752
and the Gregorian calendar for dates from September 14, 1752 through
December 31, 9999 as though the Gregorian calendar had been adopted on
September 14, 1752.
The following operands shall be supported:
month Specify the month to be displayed, represented as a decimal
integer from 1 (January) to 12 (December). The default shall be
the current month.
year Specify the year for which the calendar is displayed, repre‐
sented as a decimal integer from 1 to 9999. The default shall be
the current year.
The following environment variables shall affect the execution of cal:
LANG Provide a default value for the internationalization variables
that are unset or null. (See the Base Definitions volume of
IEEE Std 1003.1-2001, Section 8.2, Internationalization Vari‐
ables for the precedence of internationalization variables used
to determine the values of locale categories.)
LC_ALL If set to a non-empty string value, override the values of all
the other internationalization variables.
Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte as
opposed to multi-byte characters in arguments).
Determine the locale that should be used to affect the format
and contents of diagnostic messages written to standard error,
and informative messages written to standard output.
Determine the format and contents of the calendar.
Determine the location of message catalogs for the processing of
TZ Determine the timezone used to calculate the value of the cur‐
The standard output shall be used to display the calendar, in an
The standard error shall be used only for diagnostic messages.
The following exit values shall be returned:
0 Successful completion.
>0 An error occurred.
CONSEQUENCES OF ERRORS
The following sections are informative.
refers to A.D. 83, not 1983.
A future version of IEEE Std 1003.1-2001 may support locale-specific
recognition of the date of adoption of the Gregorian calendar.
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 CAL(1P)