想在 windows 用都可以的, here is:
1. download ipcalc.pl from http://jodies.de/ipcalc
2. download activeperl from http://www.activeperl.com
3. install activeperl just click "Next" and "Finish" XD
4. move the ipcalc.pl file to c:\perl
5. open the command prompt
6. cd c:\perl
7. pl2bat ipcalc.pl
8. thats it!
