Instance Property


Issues a READ_FORMAT_CAPACITIES command to the device as defined in MMC-2.


IOReturn (*ReadFormatCapacities)(void *self, void *buffer, SCSICmdField2Byte bufferSize, SCSITaskStatus *taskStatus, SCSI_Sense_Data *senseDataBuffer);



Pointer to an MMCDeviceInterface for one IOService.


Pointer to the buffer where the mode sense data should be placed.


Size of the buffer.


Pointer to a SCSITaskStatus to get the status of the SCSITask which was executed. Valid SCSITaskStatus values are defined in SCSITask.h


Pointer to a buffer the size of the SCSI_Sense_Data struct found in SCSICmds_REQUEST_SENSE_Defs.h. The sense data is only valid if the SCSITaskStatus is kSCSITaskStatus_CHECK_CONDITION.

Return Value

Returns kIOReturnSuccess if successful, kIOReturnNoDevice if there is no connection to an IOService, kIOReturnNoMemory if a SCSITask couldn't be created, or kIOReturnExclusiveAccess if the device is already opened for exclusive access by another client.


Once an MMCDeviceInterface is opened the client may send this command to get format capacity information from the media.

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