site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com -- Terry On Jul 23, 2009, at 7:04 AM, mlists@ugsoft.de wrote: Am 23.07.2009 um 13:26 schrieb Terry Lambert: It states: Uwe _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... Sorry, my answer on the driver was incorrect. Apparently some of the documentation on <http://developer.apple.com> is out of date, and the only supported way to access some of these devices is through a user client. I guess the last time I used SCSI tapes on Mac OS X (to read some old QIC tapes on a Blue and White G3), I had installed your company's ES- Backup product <http://www.ugsoft.de> to get device shims and forgot about it! Did you go to <http://developer.apple.com> and read the document "SCSI Architecture Model Device Interface Guide"? "By design, Mac OS X does not allow applications to send SCSI or ATA commands to storage devices unless the application developer also provides an in-kernel device driver that supports the commands." One of the intents if this is to allow the driver to model state for such coomands such that the state if the device is known to the driver at all times. For standard tape devices, you should not need to write your own driver; if you plug the device in, it will show up in /dev, Never seen a tape drive, neither SCSI, FireWire, USB nor FibreChannel connected to Mac OS X 10.2 up to 10.5 which shows up in /dev. What device filename should I look for? and you can at least issue reads, writes, and standard commands, such as causing a rewind, via the device file. For non-standard commands, such as you would use to control loading and unloading tapes in a tape robot, etc., you will need to write an in-kernel driver that knows how to talk to the hardware and subclasses the more generic device (i.e. the IOKit model lets you write only the missing pieces implementing the missing control commands; you don't write a whole driver that implements read/write/etc.). Instead we use SCSITaskDeviceInterface functions from userland as described in Apple's SCSI Architecture Model Device Interface Guide "WorkingWithSAM.pdf" in order to implement a "SCSI pass-thru" functionality. No additional driver required. This email sent to site_archiver@lists.apple.com