Get a list of network interfaces in PHP?

Hi All,

I've got a utility I'm working on, and I want to be able to list for
the user all the current network interfaces on the machine. Is there a
way to do this in PHP? PHP 5.0.3, Mandriva Linux 2005 (2.6 kernel).
I'm not actually in front of the machine in question, and I don't
recall the minor kernel version, or the minor version of Mandriva...

Any thoughts? I'd prefer not to have to run the script as root,
incidentally. I realize I could run as root and then just parse the
output of ifconfig, but I assume there's a more intelligent way to go
about what I'm trying to do.

The purpose of this utility is to allow me to issue a ping, from a
specified interface (including virtual interfaces, e.g., eth0:1), and
test for connectivity from the webserver to the the address i am
pinging, through the specified network interface (rather than always
pinging from the default/primary interface of the machine).

Any thoughts? How would I go about this? I haven't been able to come
up with a way to do this, short of running as root and parsing
ifconfig, as I mentioned above.

-Josh