19 May
2003
19 May
'03
12:18 p.m.
Under 2.4.x kernel (or earlier), burning CDs (and possibly ripping audio
CDs too) needs access to the "generic scsi" device for the drive (don't
you love those violent terms for copying data?). Conventionally called
/dev/sg0, device (21,0). The "0" may be another number if you have
multiple real or emulated SCSI devices. I'm not sure, but I think this
may change in the 2.6 kernel series.
If some of the applications you are using are installed with set-uid,
(perhaps on a helper program rather than the main one), that would
explain why similar actions may only work as user root in one
application, but work as a normal user in another application.
On Sun, 2003-05-18 at 13:03, derek holzer wrote:
i've been having a bit of trouble with playing and
ripping CDs, maybe
someone here can help?
i'm running Debian on a laptop, and as root i don't have any serious
problems doing either, but as a user it becomes a bit wierd... let me
explain...
as user, i am in groups cdrom and disk. i have set permissions as follows:
in /dev:
lr-xr-xr-x 1 root root 13 May 18 17:31 cdrom ->
cdroms/cdrom0
drwxr-xr-x 1 root root 0 Jan 1 1970 cdroms
in /dev/cdroms
lr-xr-xr-x 1 root root 34 Jan 1 1970 cdrom0 ->
../scsi/host1/bus0/target0/lun0/cd
in /dev/scsi/host1/bus0/target0/lun0/
brw-rw-rw- 1 root cdrom 11, 0 Jan 1 1970 cd
i have none of these other cdrom devices listed in /dev:
/dev/hdc
/dev/sr0
/dec/scd0
but my drive appears to be ATAPI with SCSI emulation. i have added the
following to my /etc/lilo.conf to reflect this:
append="hdc=ide-scsi"
although commenting this out doesn't seem to do much.
i can rip CDs as a user with Grip, but RipperX tells me i need
permission to access the CD drive [cannot open cdrom drive]. i can play
CD audio with Alsaplayer, but not with XMMS. likewise, xfreecd doesn't
find the drive, but workman does. very inconsistant! running cdparanoia
-vQ as user gives the following:
Checking /dev/cdrom for cdrom...
Testing /dev/cdrom for cooked ioctl() interface
/dev/scsi/host1/bus0/target0/lun0/cd is not a cooked ioctl CDROM.
Testing /dev/cdrom for SCSI interface
No generic SCSI device found to match CDROM device
/dev/scsi/host1/bus0/target0/lun0/cd
it seems that there are still some permissions to change somewhere, but
i can't for the life of me figure out where!
what have i missed?
thanks,
derek
--
sigmotto: Liberty is theft.