Wireshark-users: Re: [Wireshark-users] UDP port range in Tshark
From: Guy Harris <[email protected]>
Date: Tue, 1 Dec 2009 12:34:45 -0800
On Dec 1, 2009, at 9:26 AM, Boaz Galil wrote:

The problem is when I want to use the same command for UDP e.g : “" -f "host x.x.x.x and ((udp [2:2] >= 20 and udp [2:2] <= 80) or (udp [0:2] >= 20 and udp [0:2] <= 80))" I am not getting any error but I am also not getting any results inside the packet capture file.
Are you getting any traffic to or from UDP ports 20 through 80 on your  
network?
(BTW, newer versions of libpcap support "host x.x.x.x and {tcp,udp}  
portrange 20-80".)