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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 converstion 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.