Add VTY command to immediately expire user (set expire_lu to now)

[Keith]

Hi all,

( so.. by way of finding out what is the best way to do this kind of
thing, I went ahead and submitted my patch to gerrit. )

I've added a command to the vty to set the expire_lu value for the
subscriber to now.

My personal use case for this is that I wanted a way to set lac =
GSM_LAC_RESERVED_DETACHED when I know that the MS is not there, (because
I know it has gone to another nitb with a different lac) and therefore I
no longer want to page it and I also don't want it showing up as
connected when I poll the hlr for lac>0 via sqlite3. So if I set the
expire_lu to now, openbsc will very shortly afterwards, issue

<0002> gsm_subscriber.c:366 Expiring inactive subscriber......

I'm not sure if this would be considered something anybody else might
want, or confusing for users, and I haven't fully tested (yet) what
might happen if the mobile has not in fact done an IMSI attach to
another lac yet I expire it.

Also, my C programming history is nill. I have no idea if setting a
time_t to time(0) is cool, or will result in sky falling down.
I'm not quite sure if it's necessary to call subscr_put()
I also realise I left a pointless rc declaration in there. oh well..
guess I learn about submitting patch set 2..

So the unwritten question is, with ideas like this, should I first ask
here on the list for opinion on the theoretical merits or not of such an
idea, or should I just submit to gerrit and should the discussion, if
any, happen there?

Many Thanks!

k/