This hasn't been "reserved for future use" since Linux 2.6.22 (commit
83b496e928db ("[RTNETLINK]: Allow changing of subsets of netdevice
flags in rtnl_setlink")), and it's used by iproute2.

Signed-off-by: Alyssa Ross <hi@alyssa.is>
---
 man/man7/rtnetlink.7 | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/man/man7/rtnetlink.7 b/man/man7/rtnetlink.7
index 56cb79bca..6e873dc71 100644
--- a/man/man7/rtnetlink.7
+++ b/man/man7/rtnetlink.7
@@ -83,7 +83,9 @@ is the unique interface index
 message, thus creating a link with the given
 .IR ifindex );
 .I ifi_change
-is reserved for future use and should be always set to 0xFFFFFFFF.
+is a mask specifying which bits of
+.I ifi_flags
+should be applied to the device.
 .TS
 tab(:);
 c s s

base-commit: 46950a0845de91c422efe6c639091ace42cb92f8
-- 
2.51.0

Hi Alyssa,

On Thu, Dec 18, 2025 at 07:54:52PM +0100, Alyssa Ross wrote:
> This hasn't been "reserved for future use" since Linux 2.6.22 (commit

lol!

> 83b496e928db ("[RTNETLINK]: Allow changing of subsets of netdevice
> flags in rtnl_setlink")), and it's used by iproute2.
> 
> Signed-off-by: Alyssa Ross <hi@alyssa.is>

Thanks!  I've applied the patch.


Have a lovely night!
Alex

> ---
>  man/man7/rtnetlink.7 | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/man/man7/rtnetlink.7 b/man/man7/rtnetlink.7
> index 56cb79bca..6e873dc71 100644
> --- a/man/man7/rtnetlink.7
> +++ b/man/man7/rtnetlink.7
> @@ -83,7 +83,9 @@ is the unique interface index
>  message, thus creating a link with the given
>  .IR ifindex );
>  .I ifi_change
> -is reserved for future use and should be always set to 0xFFFFFFFF.
> +is a mask specifying which bits of
> +.I ifi_flags
> +should be applied to the device.
>  .TS
>  tab(:);
>  c s s
> 
> base-commit: 46950a0845de91c422efe6c639091ace42cb92f8
> -- 
> 2.51.0
> 

-- 
<https://www.alejandro-colomar.es>