CAN support was introduced with issue #10141. Python still seems to lack support for CAN FD which is available with the socket option CAN_RAW_FD_FRAMES, see here (chapter 4.1.5): https://www.kernel.org/doc/Documentation/networking/can.txt

Annoying.
I thought CAN_RAW_FD_FRAME would be a macro, which would have made conditional compilation easy, but it's apparently a enum value, which means we have to add a configure-time check...

I have added a patch to update this with conditional compilation.

To show where I got my sources: https://github.com/torvalds/linux/commit/e2d265d3b587f5f6f8febc0222aace93302ff0be

There does not appear to be any new structures needed other than supporting the constant.

LGTM, just adding Antoine (the expert for the socket module).  I'm ready to commit over here.

The new constant should probably be added to https://docs.python.org/3/library/socket.html#constants (with a .. versionadded:: 3.5 directive)

I am not going to be able to write docs on this because I am not totally sure how you would use this; There is an entry in the docs for CAN_* so that might be enough. I have a line now saying that this particular flag is available as of 3.5 though.

Follow the instructions in this:

https://docs.python.org/devguide/docquality.html

And make it look something like this:

https://docs.python.org/3/library/socket.html#socket.CAN_BCM

I tried to provide a summary of the Linux page on the topic and then said that it was fully documented there.

New changeset 03ff92b26fa9 by Larry Hastings in branch 'default':
Issue #22631: Added Linux-specific socket constant CAN_RAW_FD_FRAMES.
https://hg.python.org/cpython/rev/03ff92b26fa9

Patch committed. Thanks, Joe!

it would be nice to have these constants backported to both 2.7 and 3.4. It may be good to check for other missing consgtants in this module in 2.7 and 3.4.

So I think the patch could be applied to 3.4; I will look into moving the other back sometime this week.

Isn't this a "new feature"?  2.7 is maybe fair game, but 3.4 arguably is not.

It should be odd to have a field marked in the documentation as "New in 3.4.4."

It is a new feature.

Benjamin, would you like CAN_RAW_FD_FRAMES in the next 2.7?

There is no CAN support in 2.7, so no.