Change the timestamp of a file in Ruby

This is somewhat similar to the touch command of Linux:

CopyFileUtils.touch 'example.txt', :mtime => Time.now - 2.hours

If you omit the :mtime the modification timestamp will be set to the current time:

CopyFileUtils.touch 'example.txt'

You may also pass an array of filenames:

CopyFileUtils.touch %w[ foo bar baz ], :mtime => Time.now - 2.hours

Non-existent files will be created.