Adding one month (30-31 days) in UNIX SOLARIS

#! /usr/bin/ksh

d=`date +%d`

m=`date +%m`

y=`date +%Y`

if [ $m%2 -eq 0 ]

then

d1=`expr $d + 30`

d=expr $d1 - 30`

else

d1=`expr $d + 31`

d=expr $d1 - 31`

fi

if [ $m -eq 12 ]

then

y=`expr $y + 1`

m=0

fi

m=`expr $m + 1`

if [ $m -lt 10 ]

then

m=0$m

fi

echo "$y-$m-$d"

exit 0