_RegSetValueEx

include vmm.h

LONG _RegSetValueEx(HKEY hkey, LPTSTR lpszValueName, 
    DWORD dwReserved, DWORD fdwType, LPBYTE lpbDta, DWORD cbData)
 

Stores data in the value field of an open registry key; the service can also set additional value and type information for the given key. See the documentation for the Win32 function of the same name for additional information.

• Returns ERROR_SUCCESS if the function succeeds. Otherwise, an error code is returned, possibly one of the following:

hkey

Handle of the open key or one of these predefined values:

HKEY_CLASSES_ROOT

HKEY_CURRENT_USER

HKEY_LOCAL_MACHINE

HKEY_USERS

lpszValueName

Points to a null-terminated string containing the name of the value to set. If a value with this name is not already present in the key, the function adds it to the key. If this parameter is NULL or points to an empty string, the fdwType must be REG_SZ and this service will set the same value as RegSetValue.

lpdwReserved

Reserved; must be NULL.

fdwType

The type code for the value entry. It can be one of these values:

REG_BINARY	Binary data in any form.
REG_SZ	A null-terminated UNICODE or ANSI string.

lpbData

Address of buffer that receives the data for the value entry.

lpcbData

Address of variable that specifies size, in bytes, of the buffer addressed by lpbData. If the type is REG_SZ this must include the terminating null character.

If the key specified by lpszSubKey does not exist, this service will create it.

Value lengths are limited by available memory. Long values (more than 2048 bytes) should be stored as files with the filenames stored in the registry.

Of the predefined key values, only HKEY_LOCAL_MACHINE is available to VxDs during initialization time. The entire registry space can only be accessed after VxD initialization is complete.