Wireshark · Ethereal-users: Re: [Ethereal-users] Ethereal GUI cannot see interface in capture dialogue but can still capture on

["Guy Harris" <gharris@xxxxxxxxx>]

Jeff wrote:
>  Can anyone offer a suggestion on how to remedy this - I know I can
> workaround it by capturing to a file and reading it into the GUI,

...or by just typing "ath0" into the "Interface" box in the Capture
Options window in Ethereal - just as Tethereal lets you capture on an
adapter that doesn't show up in "tethereal -D", Ethereal lets you capture
on an adapter that doesn't show up in the drop-down list (which comes from
the same source as the "-D" list).

> but I am interested to fix the underlying issue.
>
> Tried to google it for a while and found an old post about whether or not
> pcap was looking in /proc/net/dev

Whether it does that on a Linux system depends on whether it gets a list
of interfaces with SIOCGIFCONF (which returns only interfaces with IP
addresses, so it looks through /proc/net/dev to find other interfaces) or
with getifaddrs() (which was presumed to return all interfaces, but that
might not be the case).

What happens if you run "strace -o /tmp/getaddrs tethereal -D"?  What
system calls is Tethereal making?

Also, what does "tcpdump -D" report?