Now that I know how to insert that part of code in a for I understood that it doesn't work correctly.
Example: MacBook-di-Mirko:unix mirko$ ./test.sh
/Users/mirko/Unix/file.txt
/Users/mirko/Unix/Happy.txt
/Users/mirko/Unix/lettera.txt
/Users/mirko/Unix/motion/README.txt
Ok.
But, another example: (after I changed the files)
MacBook-di-Mirko:unix mirko$ ./test.sh
/Users/mirko/Unix/file.txt
/Users/mirko/Unix/Happy.txt
/Users/mirko/Unix/lettera.txt
/Users/mirko/Unix/motion/README.txt
MacBook-di-Mirko:unix mirko$ ./test.sh
/Users/mirko/Unix/file.txt
/Users/mirko/Unix/lettera.txt
/Users/mirko/Unix/motion/README.txt /Users/mirko/Unix/Radio Ga
Ga.txt
/Users/mirko/Unix/Save
Me.txt
/Users/mirko/Unix/Seven
Seas
Of
Rhye.txt
So the files with a space " " in their name are splitted in two lines.