Am 15.05.21 um 20:42 schrieb Kurt Van Dijck:
> On Sat, 15 May 2021 18:10:20 +0000, Patrick Menschel wrote:
>> Am 15.05.21 um 16:01 schrieb Patrick Menschel:
>>> Am 15.05.21 um 14:26 schrieb Kurt Van Dijck:
>>>> On Fri, 14 May 2021 12:04:47 +0000, Patrick Menschel wrote:
>>>>> Do I need to open one socket per PGN I'm sending?
>>>>> e.g.
>>>>>
>> Guess I have to amend that impression, everything works fine,
>> except for broadcast which gives me a PermissionError ?!
>
> Will you not forget to set the SO_BROADCAST socket option ( see: man 7 socket )
>
Thank you both,
that was the trick. But why does it throw a PermissionError ?
I would expect a ValueError, e.g. -EINVAL because I as a User did the
wrong input or rather did not set a socket option.
Alternatively -EPROTO.
python -i
Python 3.9.5 (default, May 13 2021, 13:29:45)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import socket
>>> s = socket.socket(socket.AF_CAN, socket.SOCK_DGRAM, socket.CAN_J1939)
>>> s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, True)
>>> s.bind(("mcp0", 0, 0x40000, 0x20))
>>> s.sendto(bytes(range(8)), ("mcp0", 0, 0xFECA, 0xFF))
8
>>> s.sendto(bytes(range(64)), ("mcp0", 0, 0xFECA, 0xFF))
64
>>>
candump mcp0
mcp0 18FECA20 [8] 00 01 02 03 04 05 06 07
mcp0 18ECFF20 [8] 20 40 00 0A FF CA FE 00
mcp0 18EBFF20 [8] 01 00 01 02 03 04 05 06
mcp0 18EBFF20 [8] 02 07 08 09 0A 0B 0C 0D
mcp0 18EBFF20 [8] 03 0E 0F 10 11 12 13 14
mcp0 18EBFF20 [8] 04 15 16 17 18 19 1A 1B
mcp0 18EBFF20 [8] 05 1C 1D 1E 1F 20 21 22
mcp0 18EBFF20 [8] 06 23 24 25 26 27 28 29
mcp0 18EBFF20 [8] 07 2A 2B 2C 2D 2E 2F 30
mcp0 18EBFF20 [8] 08 31 32 33 34 35 36 37
mcp0 18EBFF20 [8] 09 38 39 3A 3B 3C 3D 3E
mcp0 18EBFF20 [8] 0A 3F FF FF FF FF FF FF
Best Regards,
Patrick
