Hello, I think you didn't get the point. When writing the CD it is done in raw mode and you don't need to mount. So the permissions given during mounting doesn't matter. Hope that helps. Arko
On Fri, 2005-07-22 at 18:46, Linux Lover wrote: > Thank you Manas, for your response. > > I think I am getting your point but still I have some confusion, if you > can discuss more in detail it will certainly help me to understand this > thread. First let me tell you what I have understand. From your write > up, it is clear that writing over a CD-R is a write-once technology. > When files are written to a CD-R disk they can't be modified and the > disk can't be erased. The ISO9660 file system is first created on the > hard disc and then it is transfered to the CD-R media, right? No problem > up to this. Still I think my question is not answered..............my > question is, as the OS itsef determines the Recorder Drive as Read Only > device, how the device is getting the write permission from the OS to > start a write process. Is linux gives permission to start a write > process over a Read Only device, violating the file permission rule? > > Regards > Anindya > > Manas Laha wrote: > > > > > Linux Lover wrote: > > > >> From /etc/fstab it is transperant that a CD Writer is a device, which > >> is mounted at a certain mount point, which can access iso9660 file > >> system blah blah blah blah..... > >> > >> There is also an option for the writer which is `ro'. If the device > >> enjoyes the read only status, how do we able to write on discs? > >> > >> A typical entry for the device is as follows : > >> /dev/cdrom /mnt/cdrom iso9660 noauto,owner,ro 0 0 > >> > >> From the above it is clear that the device do not have a write > >> permission. Still it writes, how? > >> > >> Regards > >> Anindya Banerjee > > > > > > > > The filesystem on a random access medium has to be mounted only if > > access to it is desired through the usual commands: ls, cp, mv, > > read(), write() etc. > > > > With magnetic media the usual practice is to create a filesystem by > > the process called formatting and then write/read files using commands > > like those above. > > > > Due to its nature, a CD-R must be written to all at once, which means > > we cannot do this 2-step process with CD-Rs (although this is changing > > with CD-RWs). Instead, the iso9660 filesystem is created as a file on > > a different medium (a hard disk, usually) and then this file is > > written to the CD in _raw_ mode. The CD does not have to be mounted > > for raw mode access. (Indeed, it should not be mounted immediately > > before being written on.) > > > > Does this answer your question? > > > > - Manas Laha > > > > > > ***************************************** > > This Mail is Certified to be Virus Free. > > CIC Network Security Group, IIT Kharagpur > > ***************************************** > > > > -- > > To unsubscribe, send mail to [EMAIL PROTECTED] with the body > > "unsubscribe ilug-cal" and an empty subject line. > > FAQ: http://www.ilug-cal.org/node.php?id=3 > > > > > -- > To unsubscribe, send mail to [EMAIL PROTECTED] with the body > "unsubscribe ilug-cal" and an empty subject line. > FAQ: http://www.ilug-cal.org/node.php?id=3 -- To unsubscribe, send mail to [EMAIL PROTECTED] with the body "unsubscribe ilug-cal" and an empty subject line. FAQ: http://www.ilug-cal.org/node.php?id=3
