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Wireshark-dev: Re: [Wireshark-dev] Get "Malformed Packet" for 802.11 Beacon frames on Windows

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Tue, 12 Apr 2016 19:26:24 -0700
On Apr 12, 2016, at 7:11 PM, Guy Harris <guy@xxxxxxxxxxxx> wrote:

> You *are* controlling monitor mode based on whether pcap_set_rfmon_mode() was called before pcap_activate(), right? If not, you should do so.

That's pcap_set_rfmon(), and you determine whether it was called by looking at the "opt.rfmon" field in the pcap_t that was passed to your activate routine.