# File lib/net/ssh/ruby_compat.rb, line 26
      def self.io_select(*params)
        # It should be safe to wrap calls in a mutex when the timeout is 0
        # (that is, the call is not supposed to block).
        # We leave blocking calls unprotected to avoid causing deadlocks.
        # This should still catch the main case for Capistrano users.
        if params[3] == 0
          SELECT_MUTEX.synchronize do
            IO.select(*params)
          end
        else
          IO.select(*params)
        end
      end