Re: CVS commit: src/sys/arch/xen/xen

[Taylor R Campbell <campbell+netbsd%mumble.net@localhost>]

   Date: Mon, 04 Apr 2011 23:46:19 +0200
   From: Jean-Yves Migeon <jeanyves.migeon%free.fr@localhost>

   The newer scripts for Xen read the interface value from the vifname
   entry in Xenstore, so changing the name is not that critical. But this
   should be stabilized sooner than later. Personally, I find '_' rather
   ugly in an interface name... but I am open to suggestions, even fixing
   rc.d/network if it needs to.

One could declare that ifnames must match [a-z][-a-z0-9]*[0-9], and
then in /etc/rc.d/network pass them through `tr - _' before evaluating
`args=\$ifconfig_$int'.  This guarantees that setting ifconfig_ifN in
/etc/rc.conf always works, and depends only on agreeing to the ifname
policy and ensuring that all the existing ifnames actually follow it.

Of course, tr might not be available yet in /etc/rc.d/network, but
someone wizardlier (or more patient) with sh than I can probably work
around that...