readCD()
Declaration
#ifdef __LP64__
virtual IOReturn readCD(
IOService *client,
UInt64 byteStart,
IOMemoryDescriptor *buffer,
CDSectorArea sectorArea,
CDSectorType sectorType,
IOStorageAttributes *attributes = 0,
UInt64 *actualByteCount = 0);
#else /* !__LP64__ */
virtual IOReturn readCD(
IOService *client,
UInt64 byteStart,
IOMemoryDescriptor *buffer,
CDSectorArea sectorArea,
CDSectorType sectorType,
UInt64 *actualByteCount = 0);
#endif
/* !__LP64__ */Parameters
- client:
Client requesting the read.
- byteStart:
Starting byte offset for the data transfer (see sectorArea parameter).
- buffer:
Buffer for the data transfer. The size of the buffer implies the size of the data transfer.
- sectorArea:
Sector area(s) to read. The sum of each area's size defines the natural block size of the media for the call. This should be taken into account when computing the address of byteStart. See IOCDTypes.h.
- sectorType:
Sector type that is expected. The data transfer is terminated as soon as data is encountered that does not match the expected type.
- attributes:
Attributes of the data transfer. See IOStorageAttributes.
- actualByteCount:
Returns the actual number of bytes transferred in the data transfer.
Return Value
Returns the status of the data transfer.
Overview
Read data from the CD media object at the specified byte offset into the specified buffer, synchronously. Special areas of the CD sector can be read via this method, such as the header and subchannel data. When the read completes, this method will return to the caller. The actual byte count field is optional.