Doubt in print_802_11.c

["Latha G" <lathajee () gmail com>]

Hi all,

I read in tcpdump manpage that it supports WLAN.
My campus LAN is ethernet, so I want to see how the WLAN o/p will be, for
that I am seeing print_802_11.c
In that some of the Macros are like this

#define    FC_VERSION(fc)        ((fc) & 0x3)
#define    FC_TYPE(fc)        (((fc) >> 2) & 0x3)
#define    FC_SUBTYPE(fc)        (((fc) >> 4) & 0xF)
#define    FC_TO_DS(fc)        ((fc) & 0x0100)
#define    FC_FROM_DS(fc)        ((fc) & 0x0200)
#define    FC_MORE_FLAG(fc)    ((fc) & 0x0400)
#define    FC_RETRY(fc)        ((fc) & 0x0800)
#define    FC_POWER_MGMT(fc)    ((fc) & 0x1000)
#define    FC_MORE_DATA(fc)    ((fc) & 0x2000)
#define    FC_WEP(fc)        ((fc) & 0x4000)
#define    FC_ORDER(fc)        ((fc) & 0x8000)

fc is frame control.
As i know, FC structure is like
[ Version Type Subtype ToDs FromDS MF Retry Pwr More W O]

Since FC is a 16-bit field, to obtain Version field  fc &cooo,
this is enough...but what i am seeing was completely different....
If we reverse the FC fields , then above code will be supported...

Please assist me in understanding this...

Thanks in advance..

--
Regards,
Latha.
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