docs: def set_nonblock(self, set_flag=True):
          """Set the non blocking flag on the socket"""
  
          # Get the current flags
          if self.fd_flags is None:
              try:
                  self.fd_flags = fcntl.fcntl(self.ins, fcntl.F_GETFL)
              except IOError:
                  warning("Cannot get flags on this file descriptor !")
                  return
  
          # Set the non blocking flag
          if set_flag:
              new_fd_flags = self.fd_flags | os.O_NONBLOCK
          else:
              new_fd_flags = self.fd_flags & ~os.O_NONBLOCK
  
          try:
              fcntl.fcntl(self.ins, fcntl.F_SETFL, new_fd_flags)
              self.fd_flags = new_fd_flags
          except Exception:
              warning("Can't set flags on this file descriptor !")