#!/bin/ksh
###########################################################################
# Date calculations using Korn shell (ksh88)
# Tapani Tarvainen July 1998, May 2000
# This code is in the public domain.
# Julian Day Number from calendar date
date2julian()   #  day month year
{
  typeset -i day month year tmpmonth tmpyear
  day=$1;  month=$2;  year=$3
  ((tmpmonth = 12 * year + month - 3))
  ((tmpyear = tmpmonth / 12))
  print $(( (734 * tmpmonth + 15) / 24 -  2 * tmpyear + \
    tmpyear/4 - tmpyear/100 + tmpyear/400 + day + 1721119 ))

}

###
# Matt's Added formatting
###

# Store input dates
date1=$1
date2=$2

# Get the dates into their respective fields.  Uncomment the format of
# date input being used.

# YYYYMMDD
year1=${date1%????}; mmdd1=${date1#????}; month1=${mmdd1%??}; day1=${mmdd1#??}
year2=${date2%????}; mmdd2=${date2#????}; month2=${mmdd2%??}; day2=${mmdd2#??}

# YYYY/MM/DD  or YYYY/M/D
#print $date1 |IFS=/ read year1 month1 day1
#print $date2 |IFS=/ read year2 month2 day2

# MM/DD/YY    or M/D/YYYY
#print $date1 |IFS=/ read month1 year1 day1
#print $date2 |IFS=/ read month2 year2 day2

# Calculate and print the difference between dates (date2 - date1)
print -- "$(($(date2julian $day2 $month2 $year2) - $(date2julian $day1 \
$month1 $year1)))"