You use 'ioreg' to list the devices on your system:

    bash$ ioreg | head
    +-o Root  <class IORegistryEntry, retain count 11>
      +-o PowerBook5,2  <class IOPlatformExpertDevice, registered, matched, active, $
        +-o MacRISC2PE  <class MacRISC2PE, !registered, !matched, active, busy 0, re$
        | +-o IOPlatformFunction  <class IOPlatformDevice, registered, matched, acti$
        | | +-o IOPlatformFunctionDriver  <class IOPlatformFunctionDriver, !register$
        | +-o IOPMrootDomain  <class IOPMrootDomain, registered, matched, active, bu$
        | | +-o IORootParent  <class IORootParent, !registered, !matched, active, bu$
        | | +-o RootDomainUserClient  <class RootDomainUserClient, !registered, !mat$
        | | +-o RootDomainUserClient  <class RootDomainUserClient, !registered, !mat$
        | | +-o RootDomainUserClient  <class RootDomainUserClient, !registered, !mat$
    bash$

So For instance to find your CDROM, you would execute:

    bash$ ioreg | grep IOCompact
 

or, more likely, if you have a drive that can read DVDs:

    bash$ ioreg | grep IODVD
        | |   |   |           +-o IODVDServices  <class IODVDServices, registered, m$
        | |   |   |             +-o IODVDBlockStorageDriver  <class IODVDBlockStorag$
    bash$ 

-- DarrellSchiebel - 15 Jun 2005