CDROM(4,F)g                  AIX Technical Reference                  CDROM(5,F)



-------------------------------------------------------------------------------
cdrom



PURPOSE

Supports the cdrom device driver.

DESCRIPTION

The cdrom device driver provides block and character access to the cdrom disks.
The cdrom special file is unique to AIX PS/2.  The minor number of this system
device is determined via the special files /dev/cdromn and /dev/rcdromn, where
n specifies the minor number.

In raw I/O, the buffer must begin on a 512 byte boundary and counts must be a
multiple of 512 bytes.  Likewise lseek system calls must specify a multiple of
512 bytes.  However, for the most efficient raw I/O, the buffer should be on a
4096 byte boundary and counts should be a multiple of 4096 (the page size).
Note that cdrom devices are read only; thus, any writes will return an error.

ioctl Operations

The IOCTYPE type ioctl call returns the value DD_CDROM, defined in
/sys/devinfo.

The IOCTYPE type ioctl call returns the structure defined in /sys/devinfo.h.

FILES

/dev/cdrom0, /dev/cdrom1, ...
/dev/rcdrom0, /dev/rcdrom1, ...

RELATED INFORMATION

In this book:  "fd" and "ioctlx, ioctl, gtty, stty."


















Processed November 7, 1990        CDROM(4,F)g                                  1