Provided by: itools_1.0-6_amd64 
NAME
ical - A Hijri/Islamic calendar (and converter)
SYNOPSIS
ical [--gregorian yyyymmdd] [--hijri yyyymmdd] [--umm_alqura] [--fixed_view] [--dual] [--help]
DESCRIPTION
The ical program is a Hijri/Islamic calendar displayer. It utilizes and includes a Gregorian to Hijri
(and vice-versa) date converter. The application uses and offers multiple calculation methods with not
all of them agreeing at all times. The reason for this multiplicity is due to not having one agreed upon
method and so various entities develop and advocate their calculations.
ical is able to comprehend and calculate both pre-epoch or pre-Hijrah, denoted as "B.H", as well as post-
epoch or post-Hijrah, denoted as "A.H", dates. ical also utilizes Gregorian's pre-epoch "B.C" and post-
epoch "A.D" dates and notes them per its output. When entering pre-epoch years, negative numbers ought
to be utilized.
ical when run without any command-line options uses the host machine's Gregorian date and converts it to
Hijri to display that month's view. Entries enclosed by [] denote exact day specified.
OPTIONS
ical follows the usual GNU command line syntax, with long options starting with two dashes (`-'). A
summary of all options is noted below:
-h, --help
Show summary of options
-g, --gregorian yyyymmdd
Specify the Gregorian date to be converted where 'y' stands for year, 'm' for month and 'd' for
day
-hi, --hijri yyyymmdd
Specify the Hijri date to be converted where 'y' stands for year, 'm' for month and 'd' for day
-u, --umm_alqura
Specify to use the Umm Al-Qura calculation method (used mostly in Saudi Arabia)
-f, --fixed_view
Show a fixed week view (ie. start on Sun and end on Sat) else default to showing the preferred
week view of the resulting calendar (Gregorian starts on Sunday, Hijri starts on Saturday)
-d, --dual
Show both conversion from and to calendar months simultaneously
BACKGROUND
The Hijri calendar is used in most of the Arab world and is the symbolic calendar of the Islamic faithed
worldwide. This calendar is known as the "Hijri" (based on the word "Hijrah" - denoting migration in
Arabic) to signal Prophet Mohammed's (PBUH) migration from Makkah to Medinah on Thursday, July 15, 622 AD
(Julian).
The Islamic Hijri calendar is strictly lunar (ie. moon-based) with twelve lunar months which do not
correspond or track their solar counterparts (the Gregorian calendar is a solar or sun-based calendar).
Lunar years and thus Hijri years are, on average, about 354 days long resulting in a Hijri year being
roughly about 11 days shorter than its Gregorian counterpart.
There is much discussion and confusion regarding how best to track the Hijri calendar. A great deal of
that confusion is based on the fact that many relay on a human moon sighting to denote the start (or end)
of a month (each month of the Hijri calendar starts when a new moon's crescent is observed or is made
visible at sunset) as opposed to using an empirical mathematic certainty. The methods presented in this
application and its underlying ITL library are strictly arithmetic in nature and do NOT take moon-phases
into consideration (in short, observational approximation is not used).
LIMITATIONS
There is currently no Umm Al-Qura support.
REPORTING BUGS
Report bugs on the web using http://bugs.arabeyes.org
AUTHOR
Written by Nadim Shaikli as part of the Arabeyes.org project.
COPYRIGHT
ical is subject to the GNU General Public License (GPL).
Copyright © 2005, Arabeyes, Nadim Shaikli.
SEE ALSO
The ITL (Islamic Tools Library). It is the underlying requirement for ical to function. The ITL library
was created and is hosted at www.arabeyes.org.