On Tue, 2004-08-31 at 17:54, Volker Kuhlmann wrote: > If the card reader is at all functional under Linux, it will be showing > up as /dev/sda, sdb, etc., one for each card slot usually. These SCSI > disks are assigned to hardware devices in order of hardware being > encountered. If you plug your card reader in and have a SCSI hard disk > system, you can have some serious fun there. If you have other USB > storage devices, exact assignment will depend on the order in which you > plug them in. (One could argue that this design of Linux is slightly > deficient.)
this is what udev is supposed to fix! http://www.linuxjournal.com/article.php?sid=7316 good intro. i suspect most distros have not fully implemented it yet. even early adopters gentoo are still saying to compile devfs into the kernel, and mount it at boot time :-) > > If you plug a memory card in the reader and the card is recognised by > Linux, the quickest way to find out where the card is in /dev/ is to run > fdisk -l, which shows the partition tables of all visible disks. Flash > cards always contain a partition table. > > Next thing you test is whether you can read data from the card in some > useful quantities. dd is the tool of choice, e.g. > > dd bs=1k if=/dev/sda of=/dev/null count=20000 > > reads the first 20 megs or so from the card. (Also good for speed > tests.) > > If there are no problems there and the card contains a valid filesystem > besides a valid partition table, you can then mount it. > > > Just been to a customer who uses pen usb devices for backup of specific > > data. Their devices ended up as /dev/sde1 and /dev/sdf1... different > > ones for different makes of pen device. > > > > My worry is that they will reset after a reboot, and start counting from > > sda1 ( well sdb1 in this case as there's a scsi disk in there). I hope not! > > You hope wrong. > > Somehow SuSE 9.1 manages to always mount the same device to the same > directory, so one can create desktop icons, but I haven't investigated > how it works. It just does. > > Volker
