Re: [Libcdio-devel] Using major/minor device numbers to determine SCSI or ATAPI

[Steven M. Schultz]

On Thu, 28 Apr 2005, R. Bernstein wrote:

> In cdparanoia on GNU/Linux there either this brilliant idea or hack to
> determine if a drive is ATAPI or SCSI by looking at the device major

        It's a hack ;)

        With a good ATAPI transport method who cares if the device
        is ATAPI or SCSI - it's all MMC{2,3} commands.  Why would the 
        application need to know (or care ;)) what the physical connector/wires
        used to transport the commands is?

> and minor number.Is this also appropriate or valid
> on on other OS's (namely FreeBSD, Solaris, BSDI, and OSX)?  

        It's not valid for BSDI that I know of - removable devices were called
        "sr" (/dev/rsr0c) for example without regard to the SCSI'ness.   Thus
        a SCSI CD/DVD drive would be 'sr0' but so would an ATAPI CD drive.

        OSX seems to just call things "disk1", "disk2", ... in order of
        appearance -  thus the builtin DVD burner (which is ATAPI) showed up
        as 'disk2' while the IEEE1394 external burner popped up as 'disk5' .

        Don't know about FreeBSD.  I do have 5.3 installed on a disk and could
        take a look one of these days.   I haven't been tempted by Solaris in
        eons - no idea what it's doing these days.

        Cheers,
        Steven Schultz