KEYBOARD_EXTENDED_ATTRIBUTES structure (ntddkbd.h)
KEYBOARD_EXTENDED_ATTRIBUTES specifies the extended attributes of a keyboard.
Syntax
typedef struct _KEYBOARD_EXTENDED_ATTRIBUTES {
UCHAR Version;
UCHAR FormFactor;
UCHAR KeyType;
UCHAR PhysicalLayout;
UCHAR VendorSpecificPhysicalLayout;
UCHAR IETFLanguageTagIndex;
UCHAR ImplementedInputAssistControls;
} KEYBOARD_EXTENDED_ATTRIBUTES, *PKEYBOARD_EXTENDED_ATTRIBUTES;
Members
Version
Type: UCHAR
The version of this structure.
Only KEYBOARD_EXTENDED_ATTRIBUTES_STRUCT_VERSION_1 supported.
FormFactor
Type: UCHAR
Keyboard Form Factor (Usage ID: 0x2C1).
| Value | Description |
|---|---|
| 0x00 | Unknown Form Factor. |
| 0x01 | Full‐Size keyboard. |
| 0x02 | Compact keyboard. Such keyboards are less than 13” wide. |
KeyType
Type: UCHAR
Keyboard Key Type (Usage ID: 0x2C2).
| Value | Description |
|---|---|
| 0x00 | Unknown Key Type. |
| 0x01 | Full‐travel keys. |
| 0x02 | Low‐travel keys such as those on laptop keyboards. |
| 0x03 | Zero‐travel or virtual keys. |
PhysicalLayout
Type: UCHAR
Keyboard Physical Layout (Usage ID: 0x2C3).
| Value | Description |
|---|---|
| 0x00 | Unknown Layout |
| 0x01 | 101 (e.g., US) |
| 0x02 | 103 (Korea) |
| 0x03 | 102 (e.g., German) |
| 0x04 | 104 (e.g., ABNT Brazil) |
| 0x05 | 106 (DOS/V Japan) |
| 0x06 | Vendor‐specific – If specified, VendorSpecificPhysicalLayout must also be specified. |
This value does not refer to the legend set printed on the keys, but only to the physical keyset layout, defined by the relative location and shape of the textual keys in relation to each other. This value indicates which of the de facto standard physical layouts to which the keyboard conforms. These layouts are commonly understood.
VendorSpecificPhysicalLayout
Type: UCHAR
A numeric identifier of the particular Vendor‐specific Keyboard Physical Layout (Usage ID: 0x2C4).
Values for this field are defined by the hardware vendor but 0x00 is defined to not specify a Vendor‐specific Keyboard Physical Layout. If non‐zero, PhysicalLayout must have value 0x06. If this identifier is 0x00, PhysicalLayout must not have the value 0x06.
IETFLanguageTagIndex
Type: UCHAR
String index of a String Descriptor having an IETF Language Tag (Usage ID: 0x2C5).
Actual string can be obtained via IOCTL_HID_GET_INDEXED_STRING IOCTL in kernel-mode drivers or HidD_GetIndexedString call in user-mode applications.
This Language Tag specifies the intended primary locale of the keyboard legend set, conformant to IETF BCP 47 or its successor.
If an appropriate IETF Language Tag is not available, such as for custom, adaptive or new layouts, the value is set to 0x00.
ImplementedInputAssistControls
Type: UCHAR
Bitmap for physically implemented input assist controls. (Usage ID: 0x2C6).
| Bit | Description |
|---|---|
| All 0 | No Keyboard Input Assist controls are implemented. |
| Bit 0 | Previous Suggestion |
| Bit 1 | Next Suggestion |
| Bit 2 | Previous Suggestion Group |
| Bit 3 | Next Suggestion Group |
| Bit 4 | Accept Suggestion |
| Bit 5 | Cancel Suggestion |
| All other bits reserved. |
Remarks
This structure is used with a IOCTL_KEYBOARD_QUERY_EXTENDED_ATTRIBUTES request to return information about the extended attributes that a keyboard supports.
This information comes from HID Keyboard Report Descriptor described in HID Usage Table Review Request 42: Consumer Page Keyboard Assist Controls.
Requirements
| Requirement | Value |
|---|---|
| Header | ntddkbd.h (include Ntddkbd.h) |
See also
IOCTL_KEYBOARD_QUERY_EXTENDED_ATTRIBUTES
IOCTL_KEYBOARD_QUERY_ATTRIBUTES
HID Usage Table Review Request 42: Consumer Page Keyboard Assist Controls