something about scan in 802.11 linux driver

HI!
   I'm working on the 802.11 linux driver now, to improve the quality of 
handoff.I have some question about the scan (probe) procedure.
   I want to begin probe earlier before the link quality is too bad, so can I
      1）control the new probe to start? maybe I should use the IO-ctl of 
SIOCSIWSCAN.
                        but where to stop the old scan procedure?
      2）Now the driver start probe for several times,but I can't find the code 
in driver.is it done at the lowwer firmware level and should i modify this?
         3）after probe ,the card decide to handoff.is this decision done in 
firmware or in software driver? can i control it?
                
     thanks !
                                                                               
Guo Jia
　　　　　　　　iamguojia-Y9sIeH5OGRo@xxxxxxxxxxxxxxxx
　　　　　　　　　　2004-06-29




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