I'm using Perl under Windows 10 if that helps.

For future reference, the version of Perl you're using is usually more pertinent than the OS or OS version. For instance, the  \K regex operator that tybalt89 uses (perhaps unnecessarily? no, there's a purpose) was introduced with Perl version 5.10. That's not likely to be a problem here since 5.10 was released (more than?) a decade ago. Just sayin'...