Unix Shell Script - Get Tomorrows Date

This code snippet will calculate tomorrows date in the format DDMMYYYY. It takes into account correct monthly overlaps and leap years etc...

Code Snippet

1.   # default output format, change as necessary
2.   defaultof="%Y%m%d"
3.  
4.   # check for input format, else use default format,
5.   # refer to 'man date' for help on format
6.   # script only supports %Y %m %d at the moment
7.   of=$defaultof
8.   [ $# -eq 1 ] && of="$1"
9.  
10.   # get today's date
11.   eval "`date +'y=%Y m=%m d=%d'`"
12.  
13.   #check for max number of days in current month
14.   days=31
15.   if [ $m -eq 4 ] || [ $m -eq 6 ] || [ $m -eq 9 ] || [ $m -eq 11 ] ; then
16.     days=30
17.   fi
18.   # check for leap year if feb
19.   if [ $m -eq 2 ]; then
20.     days=28
21.     leap1=`expr $y % 4`
22.     leap2=`expr $y % 100`
23.     leap3=`expr $y % 400`
24.     if [ $leap1 -eq 0 ] ; then
25.       if [ $leap2 -gt 0 ] || [ $leap3 -eq 0 ] ; then
26.         days=29
27.       fi
28.     fi
29.   fi
30.  
31.   # increment date
32.   if [ $d -eq $days ]; then
33.     d=1
34.     m=`expr $m + 1`
35.     if [ $m -eq 13 ]; then
36.       m=1
37.       y=`expr $y + 1`
38.     fi
39.   else
40.     d=`expr $d + 1`
41.   fi
42.  
43.   #Solaris date does not accept -d
44.   #date -d "$y-$m-$d" +"$of"
45.  
46.   eval "y=`expr $y + 0` m=`expr $m + 0` d=`expr $d + 0`"
47.   eval "y=`printf "%04d" $y` m=`printf "%02d" $m` d=`printf "%02d" $d`"
48.   tomorrowsDate="${d}${m}${y}"

End of snippet