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Wireshark-dev: Re: [Wireshark-dev] non-existant default interface

From: Fulko Hew <fhew3@xxxxxxxxx>
Date: Wed, 14 Feb 2007 10:05:41 -0500
Guy Harris wrote:

On Feb 13, 2007, at 11:51 AM, Fulko.Hew@xxxxxxxxx wrote:


The problem is that there is code in gtk/capture_dlg.c at line 677
that looks to see if you had specified an interface on the command
line, and failing that, then extract the 'capture.device' entry
from the wireshark preferences file (which is typically 'eth0')
and add that to the list of available devices, _and_ makes it the
default selection.

On my system I don't have an 'eth0',


Then how did "eth0" get made the default capture device?

That's a preference setting, so it should only have become the default capture device if you explicitly made it so. If it became so without explicitly making it so (by editing your preferences), *that's* the bug.


Good question... I don't know.

My development system is Fedora Core 5.

I looked at the wireshark RPM, and I don't see the file
mentioned in there, and I haven't found a spot in the
wireshark code where the preferences file might be auto-created
if it didn't already exist.  So I don't know how a preferences
file originally appeared in '~/.wireshark'.  Who knows...
I might have done (probably did do) a 'save preferences'
at some time in the past.

Having said all that the philisophical question still remains...

"should a non-existant interface be shown in a list of
available interfaces, even if it doesn't exist"

... regardless of whether it was specified in a preferences file,
or via an '-i' command line options switch.

Personally... I don't think it should be shown and it could
also be grounds for an error box:
"The selected interface does not exist."