Re: [gentoo-user] cdrecord - devname - was burning a dvd+r dl...

[Dale]

Joerg Schilling wrote:
> Dale <rdalek1967@×××××.com> wrote:
>
>
>>> I am sorry for my bad English.
>>> I used to run all my cdrecord commands as user. I am unable to run the
>>> command in the format using dev=scsibus,target,lun as user (I can do so
>>> as root), but I am able to burn a cd as user when using dev=/dev/cdrom.
>>> With the first method the average write speed seems to be much faster
>>> than with the second one.
>>> I just wander if this is normal behavior. I always followed
>>> http://gentoo-wiki.com/HOWTO_Create_a_DVD:Burn where it says:
>>> "[snip]Replace /<device>/ with your dvd device (for example
>>> /dev/dvd)[snip]" So the wiki seems to be wrong, isn't it?
>>>
>>>
>> Is the user you are attempting to run these commands as a member of the
>> cd and cdrw groups?  Usually if a command works as root but not a user,
>> it is a permissions problem which is fixed by being in the correct
>> group.  I say usually.
>>
>
> Not true in the case of cdrecord.
>
> The Linux kernel always needed root privs to burn media before 2004.
> In 2004 a security bug was introduced that allowed to send any SCSI
> command to any drive.
>
> In Autumn 2004 this bug was not fixed but the SCSI Linux kernel interface
> was changed in an incompatible way. Now _some_ SCSI commands work as non-root.
>
> SCSI is a try and error protocol and cdrecord checks which commands are working.
> If it is possible to burn with the limuted non-root command set, it _may_ work
> but there is a high risk for buffer underruns. In this case cdrecord believes
> that you own a really dumb burner that does not support most of the nice
> features....
>
> Jörg
>
>

So that I have a better understanding of this, if he is not a member of
the cd/cdrw group then the command would still work as a user?

Dale

:-)  :-)