docs: def parse_sysctl(text):
      ''' Parse sysctl output. '''
      lines = text.splitlines()
      results = {}
      for line in lines:
          key, _, value = line.decode('ascii').partition(': ')
  
          if key == 'hw.memsize':
              value = int(value)
  
          elif key == 'vm.swapusage':
              values = value.split()[2::3]            # every third token
              su_unit = values[0][-1].lower()         # get unit, 'M'
              PAGESIZE = 1024
              if su_unit == 'm':
                  PAGESIZE = 1024 * 1024
  
              value = [ (float(val[:-1]) * PAGESIZE) for val in values ]
  
          results[key] = value
      return results