Fix #485: reliance on system error message
Fix #485: reliance on system error message

Instead of checking the string system error message 'permission denied'
(which maybe localized, so the match fails), check $! by comparing it
to Errno::EACCES.

This fix depends on a recent File::Next that properly reports errors.
See https://github.com/petdance/file-next/pull/21

petdance/ack2,petdance/ack2,petdance/ack2,petdance/ack2,petdance/ack2,petdance/ack2,petdance/ack2,petdance/ack2