# unix

$ ./find.pl

unix file before write: \0a
win file before write: \0d\0a
unix file after rewrite: \0a
win file after rewrite: \0d\0a

# windows

E:\test>perl find.pl

unix file before write: \0a
win file before write: \0d\0a
unix file after rewrite: \0a
win file after rewrite: \0d\0a