How to remove trailing whitespace of all files recursively?

Question

How can you remove all of the trailing whitespace of an entire project? Starting at a root directory, and removing the trailing whitespace from all files in all folders.

Answer 1

Ruby:

irb
Dir['lib/**/*.rb'].each{|f| x = File.read(f); File.write(f, x.gsub(/[ \t]+$/,"")) }