Re: [iproute2][PATCH v2] tc: mirred target: do not report non-existing devices

On Sun,  2 Sep 2012 13:48:02 +0300
y@redhat.com wrote:

From: Dan Kenigsberg <redacted>

Currently, if a mirred target device is removed, `tc filter show`
does not reveal the fact. Instead, it replaces the original name of the
device with the default output of ll_map:ll_idx_n2a().

This is unfortunate, since one cannot differ between this case and a valid
mirroring target device named 'if17'.

It seems that the original code meant to report an error message in this
case, but it does not, since ll_index_to_name() never returns 0. I would
not like to bail out in case of an error, since the user would still be
interested to know what are the other details of the action.

v2: properly declare the new function ll_index_exsits()

I am okay with the concept but  "missing-if1" is still a possible
but unlikely name for a device.  Maybe better to use something more
obvious like [unknown-1] or UNKNOWN?