Re: unsure - socketCAN blocking

[Steffen Rose <ro@emtas.de>]

Hello,

> > Now my error:
> > 	write: Interrupted system call
> 
> Hm, who has interrupted the write system call? gdb?

That's my question, too.
 
> > $ ./candump can0
> 
> Please use "candump can0 any,0:0,#FFFFFFFF" to also see error messages.

Thank you.
> 
> Maybe error frames?

I see some error frames and error passive in the logs. But no busoff.

Now - (sporadic different situations):
The CAN transmit from the virtual env to the CAN, but the receiving doesn't 
work. Also the candump show only the messages transmitted by the internal 
programs, not the additional traffic on the real CAN.

> > Can I see more states about the can, can_raw or the ems_usb modules?
> 
> The stats below should tell you if you still receive messages.
> 
> > $ ip -det -stat link show can0
> > 4: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast state UNKNOWN
> > qlen 10000

Currently I see only TX packets, no RX.

> You seemed to have electrical problem on the bus. Not sure if it's
> related, though.

Possible. But also in error passive is traffic possible and now the CAN 
interface is in error active. In my case not only some messages are dropped. 
The traffic dropped in one or both directions in general.

Of course, it is possible, that the USB connection or the virtual box USB 
driver or so on is the problem! At the moment I want to analyze the problem 
and search help for this.

-- 
Mit freundlichen Grüßen / Best regards

Steffen Rose