Why perl -n0e doesn"t work on cygwin and NT

I see some differenct behavior with the perl command line options:


On solaris i've tried, it works as below:

1
2
3
^D
1
2
3
<


But cygwin, i've to type '^D' 2 times to exit the program.
On MS Windows with ActivePerl, it's more strange: it print nothing
after i type '^Z'


May you help me identify this trick?

-Todd