On 28.04.2021 12:24:32, Oliver Hartkopp wrote:
> > Maybe the way to trigger the sk_error_report(sk) we might return '-1'
> > while the error is then propagated inside errno.
>
> I added some debug print in isotpsend:
>
> diff --git a/isotpsend.c b/isotpsend.c
> index 3ea574c..c2937fa 100644
> --- a/isotpsend.c
> +++ b/isotpsend.c
> @@ -45,10 +45,11 @@
> #include <libgen.h>
> #include <stdio.h>
> #include <stdlib.h>
> #include <string.h>
> #include <unistd.h>
> +#include <errno.h>
>
> #include <net/if.h>
> #include <sys/ioctl.h>
> #include <sys/socket.h>
> #include <sys/types.h>
> @@ -252,10 +253,11 @@ int main(int argc, char **argv)
> buf[buflen] = ((buflen % 0xFF) + 1) & 0xFF;
> }
>
>
> retval = write(s, buf, buflen);
> + printf("retval %d errno %d\n", retval, errno);
Note: in user space errno is only valid if retval is "-1"...
> if (retval < 0) {
> perror("write");
> return retval;
> }
>
>
> $ date +%S.%N && ./isotpsend vcan0 -s 123 -d 321 -D 44 -b && date +%S.%N
> 43.269173590
> retval 44 errno 0
> 44.271162277
>
> So it waits for the timeout as required by the '-b' option - but the errno
> is not set :-/
I'm not sure what we have to return in the kernel...
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
Attachment:
signature.asc
Description: PGP signature
