# File lib/net/ssh/connection/session.rb, line 211
211:     def preprocess
212:       return false if block_given? && !yield(self)
213:       dispatch_incoming_packets
214:       channels.each { |id, channel| channel.process unless channel.closing? }
215:       return false if block_given? && !yield(self)
216:       return true
217:     end