[Guy Harris <guy@xxxxxxxxxx>]

> When using the Ethereal Capture screen the default entry is able to 
> provide stats on the network, I want to specify an interface but cannot 
> seem to submit a proper entry.
> 
> What is the structure of a valid entry for this field?

It's a string.

What the valid strings are depends on the OS on which you're running.

On most UNIXes, "ifconfig -a" should show you the list of interfaces,
although not all of those interfaces will necessarily support packet
capture (e.g., you can't capture on loopback devices such as "lo0" on
SunOS 5.x).

The "Interface" field is a combo box; selecting the arrow-pointing-down
widget next to the text box should drop down a list of all the
interfaces that Ethereal knows about and that it can open for capturing.