Creates the specified key. If the key already exists in the registry, the call opens it.

The key that this call creates has no values. An application can use RtRegSetValueEx to set key values.

The key identified by the hKey parameter must have been opened with KEY_CREATE_SUB_KEY access. To open the key, use either this call or RtRegOpenKeyEx.

An application cannot create a key under HKEY_USERS or HKEY_LOCAL_MACHINE.

An application can use this call to temporarily lock a portion of the registry. When the locking process creates a new key, it receives the disposition value REG_CREATED_NEW_KEY, indicating that it "owns" the lock. Another process attempting to create the same key receives the disposition value REG_OPENED_EXISTING_KEY, indicating that another process already owns the lock.

LONG RtRegCreateKeyEx(
    HKEY hKey,                                     // handle to an open key
    LPCTSTR lpSubKey,                              // address of subkey name
    DWORD Reserved,                                // reserved
    LPTSTR lpClass,                                // address of class string
    DWORD dwOptions,                               // special options flag
    REGSAM samDesired,                             // desired security access
    LPSECURITY_ATTRIBUTES lpSecurityAttributes,    // address of key security structure
    PHKEY phkResult,                               // address of buffer for opened handle
    LPDWORD lpdwDisposition                        // address of disposition value buffer
);

Parameters

hKey

Handle to a currently open key or one of these predefined reserved handle values:

HKEY_CLASSES_ROOT
HKEY_CURRENT_CONFIG
HKEY_CURRENT_USER
HKEY_LOCAL_MACHINE
HKEY_USERS
HKEY_PERFORMANCE_DATA

The key opened or created by this call is a subkey of the key identified by the hKey parameter.

lpSubKey

Pointer to a null-terminated string specifying the name of a subkey that this call opens or creates. T he subkey specified must be a subkey of the key identified by the hKey parameter. This subkey must not begin with the backslash character ('\'). This parameter cannot be NULL.

Reserved

Reserved; must be zero.

lpClass

Pointer to a null-terminated string that specifies the class (object type) of this key. This parameter is ignored if the key already exists.

dwOptions

Specifies one of these special options for the key:

REG_OPTION_NON_VOLATILE	This key is not volatile; this is the default. The information is stored in a file and is preserved when the system is restarted.
REG_OPTION_VOLATILE	This key is volatile; the information is stored in memory and is not preserved when the system is restarted. This flag is ignored if the key already exists.
REG_OPTION_BACKUP_RESTORE	If this flag is set, the call ignores the samDesired parameter and attempts to open the key with the access required to backup or restore the key. If the RT Registry Server has the SE_BACKUP_NAME privilege enabled, the key is opened with ACCESS_SYSTEM_SECURITY and KEY_READ access. If the RT Registry Server has the SE_RESTORE_NAME privilege enabled, the key is opened with ACCESS_SYSTEM_SECURITY and KEY_WRITE access. If both privileges are enabled, the key has the combined accesses for both privileges.

samDesired

Specifies an access mask that specifies one of these security access levels for the new key:

KEY_ALL_ACCESS	Combination of KEY_QUERY_VALUE, KEY_ENUMERATE_SUB_KEYS, KEY_NOTIFY, KEY_CREATE_SUB_KEY, KEY_CREATE_LINK, and KEY_SET_VALUE access.
KEY_CREATE_LINK	Permission to create a symbolic link.
KEY_CREATE_SUB_KEY	Permission to create subkeys.
KEY_ENUMERATE_SUB_KEYS	Permission to enumerate subkeys.
KEY_EXECUTE	Permission for read access.
KEY_NOTIFY	Permission for change notification.
KEY_QUERY_VALUE	Permission to query subkey data.
KEY_READ	Combination of KEY_QUERY_VALUE, KEY_ENUMERATE_SUB_KEYS, and KEY_NOTIFY access.
KEY_SET_VALUE	Permission to set subkey data.
KEY_WRITE	Combination of KEY_SET_VALUE and KEY_CREATE_SUB_KEY access.

lpSecurityAttributes

This parameter must be NULL. The key gets a default security descriptor.

phkResult

Pointer to a variable that receives a handle to the opened or created key. When you no longer need the returned handle, call RtRegCloseKey to close it.

lpdwDisposition

Pointer to a variable that receives one of the following disposition values:

REG_CREATED_NEW_KEY	The key did not exist and was created.
REG_OPENED_EXISTING_KEY	The key existed and was simply opened without being changed.

Return Values

ERROR_SUCCESS

Success.

A nonzero status code defined in RTWIN32.H

Failure.

Requirements