Wireshark-users: [Wireshark-users] -z io,stat,duration,filter does not work ?

From: dikshie <dikshie@xxxxxxxxxxxxxx>
Date: Fri, 02 Nov 2007 13:56:53 +0900
hi,
i try tshark:

sfc-monitor# tshark -a duration:60 -q -z io,stat,60,ip,ipv6
Capturing on em0
34772 packets dropped
308730 packets captured

===================================================================
IO Statistics
Interval: 60.000 secs
Column #0: ip
Column #1: ipv6
                |   Column #0    |   Column #1
Time            |frames|  bytes  |frames|  bytes
000.000-060.000       0         0      0         0
===================================================================
sfc-monitor#

but io statistics give zero results.
why? any hints?

best regards,

-dikshie-