Requests feature and profile information from a CD-ROM device.
Multimedia devices have different characteristics depending on the type of media that is in the device. To provide drivers with a means of querying multimedia devices about these varying characteristics, the SCSI Multimedia - 3 (MMC-3) specification defines a command called "GET CONFIGURATION." This command permits drivers to query a device for both permanent information about the device and information that varies whenever the media changes. In Microsoft Windows 2000 and later operating systems, drivers can send this query to a device using the IOCTL_CDROM_GET_CONFIGURATION request.
The IOCTL_CDROM_GET_CONFIGURATION request returns a list of descriptors that describe the capabilities of the device for the current medium. These descriptors are divided into two groups called "feature descriptors" and "profile list descriptors." A feature specifies the capabilities of a device and its associated medium. A profile is a collection of features. If the device supports a profile, it supports all the features in the profile.
See the MMC-3 specification for further discussion concerning features and profiles.
Input Buffer Length
Parameters.DeviceIoControl.InputBufferLength in the IO_STACK_LOCATION structure indicates the size, in bytes, of the input buffer, which must be = sizeof(GET_CONFIGURATION_IOCTL_INPUT).
The driver returns the feature and profile data in the buffer at Irp->AssociatedIrp.SystemBuffer. The data begins with a header of type GET_CONFIGURATION_HEADER. Feature data is reported in the space immediately following this header. Its size and formatting depend on which features are reported.
Output Buffer Length
Parameters.DeviceIoControl.OutputBufferLength in the I/O stack location indicates the size, in bytes, of the buffer, which must be >= sizeof(GET_CONFIGURATION_HEADER).
The Information field is set to the number of bytes that are returned. The Status field is set to STATUS_SUCCESS if the request succeeds. If the Parameters.DeviceIoControl.InputBufferLength does not have the correct value, the request fails with a STATUS_INFO_LENGTH_MISMATCH error. If Parameters.DeviceIoControl.OutputBufferLength is not large enough, the request fails with a STATUS_BUFFER_TOO_SMALL error. If the value for the output buffer is too large, the request fails a STATUS_INVALID_BUFFER_SIZE message.
|Header||ntddcdrm.h (include Ntddcdrm.h)|