[sane-devel] sane-find-scanner finds multiple scanners

Douglas Gilbert dgilbert@interlog.com
Mon, 06 May 2002 23:14:20 -0400


Carsten Neumann wrote:
> On Mon, 06 May 2002, Douglas Gilbert wrote:
> 
>>Johan,
>>In your kernel config (assuming you have built that kernel)
>>turn off CONFIG_SCSI_MULTI_LUN . Some SCSI scanners don't
>>react properly to being probed for logical unit numbers (luns).
>>They should only respond to lun==0 but they respond to all
>>eight. That should leave you with:
>>   /dev/scanner
>>   /dev/sg1
>>   /dev/sgb
>>
>>Doug Gilbert
>>
> 
> Usually /dev/sga .. /dev/sgd are symlinks to /dev/sg0 .. /dev/sg3, respectively.

True, this is for backward compatibility; the /dev/sga,b,c
sequence is deprecated.

> Also most harddisks will respond at every LUN.

I hope not. Could be a problem in lk 2.5 where we support
64 bit luns :-)

> Once again, I can't see any reason why probing all LUNs will prevent the scanner from working!

It is when applications (such as SANE) send other SCSI commands
to the luns > 0 that don't exist there could be problems.

<snip/>

Doug Gilbert