code: func (n *Net) ListenUnix(nett string, laddr *net.UnixAddr) (*net.UnixListener, error) {
  	if err := n.inherit(); err != nil {
  		return nil, err
  	}
  
  	n.mutex.Lock()
  	defer n.mutex.Unlock()
  
  	// look for an inherited listener
  	for i, l := range n.inherited {
  		if l == nil { // we nil used inherited listeners
  			continue
  		}
  		if isSameAddr(l.Addr(), laddr) {
  			n.inherited[i] = nil
  			n.active = append(n.active, l)
  			return l.(*net.UnixListener), nil
  		}
  	}
  
  	// make a fresh listener
  	l, err := net.ListenUnix(nett, laddr)
  	if err != nil {
  		return nil, err
  	}
  	n.active = append(n.active, l)
  	return l, nil
  }
docs: // ListenUnix announces on the local network address laddr. The network net
  // must be a: "unix" or "unixpacket". It returns an inherited net.Listener for
  // the matching network and address, or creates a new one using net.ListenUnix.