Re: [PATCH iproute2 v2] libnetlink: check flag NLM_F_DUMP_INTR during dumps

[Eric Dumazet <eric.dumazet@gmail.com>]

On Fri, 2013-03-22 at 16:42 +0100, Nicolas Dichtel wrote:
> When this flag is set, it means that dump was interrupted and result may be
> wrong. Inform the user and let him choose to restart or not.
> 
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
> ---
> 
> v2: do not stop the dump, only display a warning
> 
>  lib/libnetlink.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/lib/libnetlink.c b/lib/libnetlink.c
> index f262959..1a882b2 100644
> --- a/lib/libnetlink.c
> +++ b/lib/libnetlink.c
> @@ -230,6 +230,10 @@ int rtnl_dump_filter_l(struct rtnl_handle *rth,
>  				    h->nlmsg_seq != rth->dump)
>  					goto skip_it;
>  
> +				if (h->nlmsg_flags & NLM_F_DUMP_INTR)
> +					fprintf(stderr,
> +						"Dump was interrupted and may be wrong.\n");
> +
>  				if (h->nlmsg_type == NLMSG_DONE) {
>  					found_done = 1;
>  					break; /* process next filter */


How many times this will be displayed ?

Please try to cook something that wont emit one warning per 8KB fetched
from the kernel ;)