I have had a bit of a read into these functions:

bgscan - Enable or disable background scanning. By default it is on so 
1. Can be turned off by setting it to 0.

bgscanidle - How often is background scanning done. Measured in 
milliseconds. By default it is set to 250. The minimum is 100. I think 
this measures how long the medium must be idle for before it begins a 
background scan. Does this include management frames. If it does then 
the medium may never be idle.

bgscanintvl - How often a background scan is performed. Measured in 
seconds. By default it is set to 300s or 5 mins. The minimum is 15 
seconds.

scanvalid - Scan cache valid threshold. By default it is 60. Not really 
sure what this does.

So, as far as my understanding goes, if you have bgscan set to 1, the 
device will perform background scanning. Once the bgscanintvl has been 
reached the device will wait until the device has been idle for 
bgscanidle.

Is this correct?

I have been playing around with these values but the "iwlist scan" and 
"wlanconfig ath0 list scan" outputs always remain the same.

Has anyone else looked into this before?

Thanks

Dave

Quoting Michael Taylor <mike.taylor@apprion.com>:

quoted text
> Did you configure the background scan and set the scanvalid cache 
> expiration ?
>
> I believe you can get what you want with iwpriv:
>
> bgscan
> bgscanidle
> bgscanintvl
> scanvalid
>
> David Murray wrote:
>> Hi,
>>
>> I have two questions. Firstly is there any difference between the 
>> "wlanconfig ath0 list scan" command and the "iwlist ath0 scan" 
>> command? Obviously their output is different but do they probe 
>> different parts of the madwifi driver?
>>
>> Secondly, is there a way to initiate a re-scan of the surrounding 
>> networks? The devices that I am playing with seem to do one scan 
>> when the interface is first brought up and then this information is 
>> cached and never re-probed.
>>
>> Any help is greatly appreciated.
>>
>> Dave
>>
>> -------------------------------------------------------------------------
>> This SF.net email is sponsored by DB2 Express
>> Download DB2 Express C - the FREE version of DB2 express and take
>> control of your XML. No limits. Just data. Click to get it now.
>> http://sourceforge.net/powerbar/db2/
>> _______________________________________________
>> Madwifi-devel mailing list
>> Madwifi-devel@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/madwifi-devel
>>
>



-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/