Function cdio_open_am_cd 

pub unsafe extern "C" fn cdio_open_am_cd(
    psz_device: *const c_char,
    psz_access_mode: *const c_char,
) -> *mut CdIo_t

Set up CD-ROM for reading. The device_name is the some sort of device name.

@return the cdio object for subsequent operations. \p NULL on error or there is no driver for a some sort of hardware CD-ROM.