Re: [PATCH] samples/bpf: Modify the incorrect format specifier

[Andrii Nakryiko]

On Thu, Dec 5, 2024 at 6:31 PM liujing <liujing@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> Replace %d with %u in snprintf() because it is "unsigned int".

The code change is fine, but the explanation is ambiguous and hard to
follow. Just mention that we are printing integers, so we need %d
instead of %u for snprintf. As you wrote it above, it reads as if we
are printing unsigned int, yet code contradicts that.

pw-bot: cr

>
> Signed-off-by: liujing <liujing@xxxxxxxxxxxxxxxxxxxx>
>
> diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
> index 266fdd0b025d..3fc1d37fee7c 100644
> --- a/samples/bpf/xdp_router_ipv4_user.c
> +++ b/samples/bpf/xdp_router_ipv4_user.c
> @@ -134,11 +134,11 @@ static void read_route(struct nlmsghdr *nh, int nll)
>                                         *((__be32 *)RTA_DATA(rt_attr)));
>                                 break;
>                         case RTA_OIF:
> -                               sprintf(ifs, "%u",
> +                               sprintf(ifs, "%d",
>                                         *((int *)RTA_DATA(rt_attr)));
>                                 break;
>                         case RTA_METRICS:
> -                               sprintf(metrics, "%u",
> +                               sprintf(metrics, "%d",
>                                         *((int *)RTA_DATA(rt_attr)));
>                         default:
>                                 break;
> --
> 2.27.0
>
>
>