Identify a mounted volume as a CD/DVD on osx

Question

When you mount anything on osx it shows up under /Volumes/mountname

Is there any way, using the commandline or C/C++ to identify the volume as a CD/DVD rom?

My current best idea goes something like this.

df | grep mountname 

to get the /dev/diskNsM path

and then

drutil | grep /dev/diskN 

to see if the path mounted device is the burner.

This works, but i'm concerned about the case where the CD/DVD is not a burner. Will it still show up in the output of drutil? Do macs even come with a non-burner CD/DVD drive?

Also i would prefer using C,C++ or objective C to do this.

I already use

const char *tmp = '/Volumes/mysterydrive';
statfs(tmp, &m);
if(m.f_flags & MNT_RDONLY)
{
    read_only = true;
}

to determine if the volume is readonly, but i cannot see if this or any related call can distinguish between a CD/DVD and a readonly mounted volume.

It would only need to work for OSX 10.5 and newer.

Any ideas?

EDIT:

Using

  diskutil info /Volumes/mysterydrive

I got the following output if its a CD/DVD

  Optical Drive Type:       CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-R, DVD-R DL, DVD-RW, DVD+R, DVD+R DL, DVD+RW
  Optical Media Type:       DVD-R
  Optical Media Erasable:   No

And that's all i need!

I'll look into using IOKit to do it programmatically later, but this seems to be the quickest way to get it done.

Answer 1

You get the most detailed information from

diskutil info /Volume/foo

In particular see Optical Drive and Optical Media entries which you only get for CD/DVDs so it is quite reliable.

Unfortunately the frameworks that diskutil uses to get all that information are private, so it will be hard to replicate it in C code.

I didn't dig deeper into other options, but since you can get the disk name from statfs it may be in theory possible to use IOKit to check out the device and you'll see IOCDMedia or IODVDMedia class if it is a CD/DVD drive (i.e. if you look for IO*Media class the BSD Name property has the disk name like disk6)