Wireshark-users: Re: [Wireshark-users] wireshark and tcpdump
From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Mon, 07 Apr 2008 12:16:57 -0700
Fabiana moreno wrote:

I need your help. I have made captures with wireshark and i was wondering if i can have the output with the same format as tcpdump?

To which format are you referring?

There are two formats that tcpdump writes - the text format that it writes if you don't use the "-w" flag, and the binary format that it writes if you use the "-w" flag. In addition, while most versions of tcpdump write out files in the "standard" libpcap format, some versions, such as versions on some older versions of some Linux distributions and the version in AIX, write a different format.

Wireshark/TShark cannot write out the same text format that tcpdump does. If, however, you save a capture from Wireshark, it will, unless you explicitly told it to use some *other* format, write the capture out in the same "standard" libpcap binary format that most versions of tcpdump write out with the "-w" flag. Similarly, TShark, when run with the "-w" flag, writes out the capture in the "standard" libpcap binary format.

If you want the tcpdump *text* format, then, if you have a Wireshark capture in binary format, have tcpdump read it, and don't pass the "-w" flag to tcpdump.