Technical data

SunOS 5.5 Ioctl Requests cdio(7I)

subcode data. The memory allocated should be a multiple of 96

bytes dependingon the transfer length.

/∗

∗ Deﬁnition of subcode structure

∗/

struct cdrom_subcode {

unsigned int cdsc_length;

caddr_t cdsc_addr;

};

The next group of I/O controls get and set variousCD-ROM drive parameters.

CDROMGBLKMODE SPARC: This ioctl() command returns the current block size used

by theCD-ROM drive. The third argument of the ioctl() call is a

pointer to an integer.

CDROMSBLKMODE SPARC: This ioctl() command requests the CD-ROM drive to

change from the current block size to the requested block size. The

third argument of the ioctl() call is an integer which contains the

requested block size.

This ioctl() command operates in exclusive-use mode only. The

caller must ensure that no other processes can operate on the same

CD-ROM device before issuing this ioctl(). read(2) behavior subse-

quent to this ioctl() remains the same: the caller is still constrained

to read the raw device on block boundaries and in block multiples.

To set the proper block size, the following values are appropriate:

CDROM_BLK_512 512 bytes

CDROM_BLK_1024 1024 bytes

CDROM_BLK_2048 2048 bytes

CDROM_BLK_2056 2056 bytes

CDROM_BLK_2336 2336 bytes

CDROM_BLK_2340 2340 bytes

CDROM_BLK_2352 2352 bytes

CDROM_BLK_2368 2368 bytes

CDROM_BLK_2448 2448 bytes

CDROM_BLK_2646 2646 bytes

CDROM_BLK_2647 2647 bytes

CDROMGDRVSPEED SPARC: This ioctl( ) command returns the current CD-ROM drive

speed. The third argument of the ioctl() call is a pointer to an

integer.

modiﬁed 26 Jan 1995 7I-59