Re: use of radiotap bit 14?

[Sam Leffler <sam-zZXckVAlHaQAvxtiuMwx3w@public.gmane.org>]

Sam Leffler wrote:
> Pavel Roskin wrote:
>> On Fri, 2007-08-31 at 00:16 +0200, Johannes Berg wrote:
>>  
>>> Our radiotap header in Linux defines bit 14 as
>>> IEEE80211_RADIOTAP_RX_FLAGS; however running wireshark on it tells me
>>> that this bit means "FCS in header". Does anybody know which use is
>>> correct, if any?
>>>     
>>
>> As far as I know, "FCS in header" is a FreeBSD thing, which came to
>> Linux in MadWifi.  "Rx flags" comes from Linux Libertas driver.
>>
>> The standard uses the later:
>> http://netbsd.gw.com/cgi-bin/man-cgi?ieee80211_radiotap+9+NetBSD-current
>>
>> MadWifi has removed the non-standard use of bit 14.  Now it's time to
>> fix wireshark.
>>
>>  
>>> Maybe we should simply skip to bit 32 or something and start redefining
>>> things properly?
>>>     
>>
>> And what would be "properly"?  How would it prevent drivers from adding
>> non-standard fields?
>>
>>   
> freebsd never had "fcs in header".

Let me rephrase.  From the CVS commit that removed it's definiteion on 
freebsd:

o remove reference to IEEE80211_RADIOTAP_FCS; it was never used, instead
  the flags are marked with IEEE80211_RADIOTAP_F_FCS to indicate whether
  or not FCS is present

I used to try and sync against other .h files.  I no longer find it useful.

    Sam