Not working; just copying the file with other name

I'm sorry, but this program seems broken... When I launch it with argument:
```bash
perl bash_obfus.pl -i testfile.sh -o testfile_obfuscated.sh
```
with the following content in the original file:
```bash
#!/bin/bash
clear
read -p 'Hi! 123. >' -n 1 dummy
exit
```
it just copies the file. What I am doing wrong?