Thanks for arriving answers!
And is 'umount' utility (non syscall!) at all exists on macosx? Can I call it at least to umount cdrom (and ask user to press the eject button manually)?
Can I invoke it like this:
system("umount $some_drom_mountpoint");
- is it always in $PATH; do all users have the right to invoke it?
Will it succeed if Finder window is opened for CDROM folder?