Copy and Paste to OS X, BSD, and Linux clipboards with Ruby.

clip.rb

class Clipboard
  CopyPaste = Struct.new :copy, :paste

  def initialize
    cmds = [['pbcopy', 'pbpaste'],
            ['xclip', 'xclip -o'],
            ['xsel', 'xsel -o']]

    cmds.map! do |cmd|
      CopyPaste.new cmd.first, cmd.last
    end

    @clipboard = cmds.find do |cmd|
      system "which #{cmd.copy} > /dev/null"
    end
  end

  def copy this
    IO.popen @clipboard.copy, 'w' do |io|
      io.print this
    end
  end

  def paste
    `#{@clipboard.paste}`
  end
end

clip = Clipboard.new

clip.copy 'hiya'
#=> nil

clip.paste
#=> "hiya"

I have tried to implement this in Linux, but when I tried to call xclip using the backtick, the program hangs.

2.0.0p247 > system 'xclip .bashrc'
 => true 
2.0.0p247 > `xclip .bashrc`
# irb hangs!

Do you have any idea what's going on? What's the difference between backtick and system? Thanks.