CM_Get_Device_ID_Size function (cfgmgr32.h)
The CM_Get_Device_ID_Size function retrieves the buffer size required to hold a device instance ID for a device instance on the local machine.
Note
In Windows Vista and later versions of Windows, the unified device property model uses the DEVPKEY_Device_InstanceId property key to represent the device instance identifier. See Retrieving a Device Instance Identifier for details.
Syntax
CMAPI CONFIGRET CM_Get_Device_ID_Size(
[out] PULONG pulLen,
[in] DEVINST dnDevInst,
[in] ULONG ulFlags
);
Parameters
[out] pulLen
Receives a value representing the required buffer size, in characters.
[in] dnDevInst
Caller-supplied device instance handle that is bound to the local machine.
[in] ulFlags
Not used, must be zero.
Return value
If the operation succeeds, the function returns CR_SUCCESS. Otherwise, it returns one of the CR_-prefixed error codes defined in Cfgmgr32.h.
Remarks
The CM_Get_Device_ID_Size function should be called to determine the buffer size required by CM_Get_Device_ID.
The size value supplied in the location pointed to by pulLen is less than MAX_DEVICE_ID_LEN, and does not include the identifier string's terminating NULL. If the specified device instance does not exist, the function supplies a size value of zero.
For information about device instance IDs, see Device Identification Strings.
For information about using device instance handles that are bound to the local machine, see CM_Get_Child.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Available in Microsoft Windows 2000 and later versions of Windows. |
| Target Platform | Universal |
| Header | cfgmgr32.h (include Cfgmgr32.h) |
| Library | Cfgmgr32.lib; OneCoreUAP.lib on Windows 10 |
| DLL | CfgMgr32.dll |