NTSTATUS
ZwSetValueKey(
IN HANDLE KeyHandle,
IN PUNICODE_STRING ValueName,
IN ULONG TitleIndex,/* optional */
IN ULONG Type,
IN PVOID Data,
IN ULONG DataSize
);
ZwSetValueKey replaces or creates a value entry for a key in the registry.
Parameters
KeyHandle
Is the handle, returned by a successful call to ZwCreateKey or ZwOpenKey, of key for which a value entry is to be written in the registry.
ValueName
Points to the name of the value entry for which the data is to be written. This parameter can be a NULL pointer if the value entry has no name. If a name string is specified and the given name is not unique relative to its containing key, the data for an existing value entry is replaced.
TitleIndex
Device and intermediate drivers should set this parameter to zero.
Type
Specifies the type of the data to be written for ValueName. System-defined types include the following:
| REG_XXX Type | Value |
| REG_BINARY | Binary data in any form |
| REG_DWORD | A 4-byte numerical value |
| REG_DWORD_LITTLE_ENDIAN | A 4-byte numerical value whose least significant byte is at the lowest address, which is identical to type REG_DWORD |
| REG_DWORD_BIG_ENDIAN | A 4-byte numerical value whose least significant byte is at the highest address |
| REG_EXPAND_SZ | A zero-terminated Unicode string, containing unexpanded references to environment variables, such as “%PATH%” |
| REG_LINK | A Unicode string naming a symbolic link; this type is irrelevant to device and intermediate drivers. |
| REG_MULTI_SZ | An array of zero-terminated strings, terminated by another zero |
| REG_NONE | Data with no particular type |
| REG_SZ | A zero-terminated Unicode string |
| REG_RESOURCE_LIST | A device driver’s list of hardware resources, used by the driver or one of the physical devices it controls, in the \ResourceMap tree |
| REG_RESOURCE_REQUIREMENTS _LIST |
A device driver’s list of possible hardware resources it or one of the physical devices it controls can use, from which the system writes a subset into the \ResourceMap tree |
| REG_FULL_RESOURCE _DESCRIPTOR |
A list of hardware resources that a physical device is using, detected and written into the \HardwareDescription tree by the system |
Device drivers need not, and should not attempt to, call ZwSetValueKey directly to write value entries in a subkey of the \Registry..\ResourceMap key. Only the system can write value entries to the \Registry..\HardwareDescription tree.
Data
Points to a caller-allocated buffer containing the data for the value entry.
DataSize
Specifies the size in bytes of the Data buffer. If Type is any of the REG_XXX_SZ, this value must include the terminating zero(s).
Return Value
ZwSetValueKey can return one of the following values:
STATUS_SUCCESS
STATUS_ACCESS_DENIED
STATUS_INVALID_HANDLE
Comments
The KeyHandle passed to ZwSetValueKey must have been opened with the KEY_SET_VALUE DesiredAccess flag set for this call to succeed. See ZwCreateKey for a description of possible values for DesiredAccess.
If the given key has no existing value entry with a name matching the given ValueName, ZwSetValueKey creates a new value entry with the given name. If a matching value entry name exists, this routine overwrites the original value entry for the given ValueName. Thus, ZwSetValueKey preserves a unique name for each value entry of any particular key. While each value entry name must be unique to its containing key, many different keys in the registry can have value entries with the same names.
Callers of ZwSetValueKey must be running at IRQL PASSIVE_LEVEL.
See Also
HalAssignSlotResources, IoAssignResources, IoQueryDeviceDescription, IoReportResourceUsage, ZwClose, ZwCreateKey, ZwFlushKey, ZwOpenKey