problem in modifying rights of a directory

[dridi0wafa]

hi,

i cant change rights of a folder although am connected as root,
i typed : chmod 777 cdrom

and it said : read only acess ,

what can i do please ?


best regards

[Irithori]

hmm,
"cdrom" sounds like there is a CD drive (or more precise its media) mounted there.
And cdrom are physically read only, so no way of changing that with chmod.

Can you please do this and post the output here:

mount

[dridi0wafa]

/dev/sda2 on /type ext3(rw)
none on /proc/bus/usb type usbdevfs (rw)
/dev/sdal on/boot type ext3 (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
none on /dev/shm type tmpfs(rw)
/dev/cdrom on/mnt/cdrom type iso9660 (ro,nosuid,nodev)


cdrom is a file under mnt under /

[Irithori]

/dev/cdrom on/mnt/cdrom type iso9660 (ro,nosuid,nodev)

Jep, as I thought:
It is a cdrom, and you cannot write to these.

[dridi0wafa]

its not a cdrom, its a file called cdrom in my redhat linux, the path is /mnt/cdrom

[Irithori]

/mnt/cdrom is a directory. ok
But a cdrom device is mounted to it (/dev/cdrom)

That device is readonly.
Therefore the directory /mnt/cdrom is readonly.

You can do the following to test that:

umount /mnt/cdrom
chown 777 /mnt/cdrom
ls -lad /mnt/cdrom
touch /mnt/cdrom/delete.me
ls -la /mnt/cdrom/
rm /mnt/cdrom/delete.me
mount /dev/cdrom /mnt/cdrom
touch /mnt/cdrom/delete.me

The second touch /mnt/cdrom/delete.me will fail.
As I said, a cdrom cannot be written to.

[its_really_me]

If your cdrom is mounted to this directory by accident, check out your settings in /etc/fstab - but usually this main directory /mnt is where mounted drives go. As you see in mount, it is mounted as filesystem type iso9660 and as read only (ro) --> you can not write to that.

[twoHats]

its not a cdrom, its a file called cdrom in my redhat linux, the path is /mnt/cdrom

Just in case you didn't believe the other two posters:

- yes cdrom is a device mounted to a file so you can access it

- the device is a CDROM - (Compact Disk Read Only Memory) which is ...ta da... read only.

Hats off to Irithori for patience way beyond the call of duty!