Shell Programming and Scripting

$ cat bst
#! /usr/bin/ksh

alias datecalc=./datecalc
function last_sunday
{
        typeset year=$1
        typeset month=$2
        typeset ldom lsom
        ldom=$(datecalc -l $year $month) || return 1
        ((lsom = ldom - $(datecalc -d $year $month $ldom)))
        echo $lsom
        return 0
}

year=$(date +%Y)
echo year = $year
for month in 3 10 ; do
        cal $month $year
        last=$(last_sunday $year $month)
        echo "last sunday is $year $month $last"
        echo
        echo
done


$
$
$ ./bst
year = 2011
     March 2011
Su Mo Tu We Th Fr Sa
       1  2  3  4  5
 6  7  8  9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31

last sunday is 2011 3 27


    October 2011
Su Mo Tu We Th Fr Sa
                   1
 2  3  4  5  6  7  8
 9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30 31
last sunday is 2011 10 30


$