# File lib/session.rb, line 574
    def clear
      stdin.puts "retall"
      stdin.puts "printf, -2, '__clear__'"
      stdin.puts "printf, -1, '__clear__'"
      stdin.flush
      while((line = stderr.gets) and line !~ %r/__clear__/o)
        raise LicenseManagerError, line if line =~ %r/license\s*manager/io
      end
      while((line = stdout.gets) and line !~ %r/__clear__/o)
        raise LicenseManagerError, line if line =~ %r/license\s*manager/io
      end
      self
    end