CDROM_SUB_Q_DATA_FORMAT structure (ntddcdrm.h)

Article
02/22/2024

The CDROM_SUB_Q_DATA_FORMAT structure is used with device control IRPs of type IOCTL_CDROM_READ_Q_CHANNEL.

Syntax

typedef struct _CDROM_SUB_Q_DATA_FORMAT {
  UCHAR Format;
  UCHAR Track;
} CDROM_SUB_Q_DATA_FORMAT, *PCDROM_SUB_Q_DATA_FORMAT;

Members

Format

Specifies which subset of the Q data the read operation should return, as follows:

IOCTL_CDROM_CURRENT_POSITION

Indicates that the read operation should return position information such as the track number, the index number, the absolute address, and the track relative address. If the IOCTL_CDROM_Q_CHANNEL device control IRP specifies this format, the information is returned in the SUB_Q_CURRENT_POSITION member of the SUB_Q_CHANNEL_DATA structure.

IOCTL_CDROM_MEDIA_CATALOG

Indicates that the read operation should return the media catalog number. If the IOCTL_CDROM_Q_CHANNEL device control IRP specifies this format, the information is returned in the SUB_Q_MEDIA_CATALOG_NUMBER member of the SUB_Q_CHANNEL_DATA structure.

IOCTL_CDROM_TRACK_ISRC

Indicates that the read operation should return the ISO/IEC 3901 Track International Standard Recording Code (ISRC). This code gives a unique number to an audio track. If the IOCTL_CDROM_Q_CHANNEL device control IRP specifies this format, the information is returned in the SUB_Q_TRACK_ISRC member of the SUB_Q_CHANNEL_DATA structure.

Track

Indicates the track number where the CD-ROM driver must read the Q subchannel data. If Format is set to IOCTL_CDROM_MEDIA_CATALOG, then the Track member must be set to zero.

Remarks

The CDROM_SUB_Q_DATA_FORMAT structure indicates the track from which to read the Q part of the subchannel data and the format of the read.

Requirements

Requirement	Value
Header	ntddcdrm.h (include Ntddcdrm.h)