Subject: Re: [PATCH] qemu tap support broken on current 3.99.17
To: None <tech-pkg@NetBSD.org>
From: Alan Barrett <email@example.com>
Date: 04/17/2006 10:55:27
On Mon, 17 Apr 2006, Hubert Feyrer wrote:
> You'll want to add some #ifdef to check that your code for a cloning
> tap(4) is really needed. As far as I understand.
> See pkgsrc/emulator/pcemu's patch-ac file, which checks __NetBSD_Version__
> against some value that indicates when (for your case) cloning tap(4)
> support was added. Finding the right value is a bit of black magic,
> looking at the CVS revision (change) history of src/sys/sys/param.h may
> help finding it.
I prefer checking for the feature itelf, rather than checking the OS
version. For example, in pkgsrc/net/openvpn, the (patched) configure
script checks for the existence of <net/if_tap.h>, and the (patched)
code that wants to use the feature checks #if defined(TAPGIFNAME).
--apb (Alan Barrett)