About filtering loopback

[dontfs]

I did not see the setting on filtering loopback, like this "setsockopt(fd, SOL_CAN_RAW, CAN_RAW_LOOPBACK, &loopback, sizeof(loopback));", how should I filter packets sent by myself, thank you.

[kurt-vd]

setsockopt(fd, SOL_CAN_J1939, CAN_J1939_RECV_OWN, ...)

[dontfs]

One of my devices has only one can interface, but I created two can sockets, one for receiving and one for sending, I set up setsockopt (fd, SOL_CAN_J1939, CAN_J1939_RECV_OWN, ...), the receiving socket can still receive information from the sending socket

[kurt-vd]

CAN_J1939_RECV_OWN behaves, just as the CAN counterpart, socket-wise. It matches only its own socket. What you try to do doesn't hold in a multi-user environment, so you better adapt the design.
You can, on reception of a message, just as the with the can_raw sockets, test the packet flags on MSG_DONTROUTE. That flag is set when the packet originated from the localhost.