On Wed. 7 Jul 2021 at 19:45, Joshua Quesenberry <engnfrc@xxxxxxxxx> wrote: > Good Afternoon, > > Do any of you know a way to check what options are valid when setting up a > CAN device with the ip link commands, either from bash or through C++? I'm > working on a piece of code that will get used on systems with varying CAN > drivers and for instance one of them doesn't support CAN-FD, so how would I > be able to know that setting the fd flag or dbitrate value would fail before > calling the setup command and seeing it fail? I would suggest to use: | ip --details link show can0 You can then parse the results to check if the data bitrate information is present. If so, it means that FD is supported. Also, the output might be easier to parse if formatted in json: | ip --details --json --pretty link show can0 Alternatively, instead of using the command line, you might prefer to directly use the kernel netlink interface to directly retrieve the different modes supported by the controller. You can refer to iproute2 source code for the how-to: https://git.kernel.org/pub/scm/network/iproute2/iproute2.git/tree/ip/iplink_can.c#n282 Yours sincerely, Vincent
