| CANLOOP(4) | Device Drivers Manual | CANLOOP(4) | 
canloop —
pseudo-device canloop
canloop pseudo interface is a loopback interface for
  the CAN layer. It can be used as destination by a CAN application, when no CAN
  hardware is available. Other sockets bound to the same
  canloop interface (or not bound to any interface) will
  receive the frames.
canloop interfaces can be created by using
    the ifconfig(8)
    create command.
canloop device appeared in NetBSD
  8.0.
| May 18, 2017 | NetBSD 9.4 |