Issue #6104 has been reported by Patrick Bennett. ---------------------------------------- Bug #6104: File.join always returns as ASCII-8BIT regardless of input encoding https://bugs.ruby-lang.org/issues/6104 Author: Patrick Bennett Status: Open Priority: Normal Assignee: Category: Target version: 1.9.3 ruby -v: ruby 1.9.3p125 (2012-02-16) [i386-mingw32] I can show lots of different variations, but the simplest proof is: irb(main):001:0> File.join('foo'.encode('utf-8')).encoding => #<Encoding:ASCII-8BIT> -- http://bugs.ruby-lang.org/