EN_STOPNOUNDO notification code
Notifies a rich edit control's parent window that an action occurred for which the control cannot allocate enough memory to maintain the undo state. A rich edit control sends this notification code in the form of a WM_NOTIFY message.
An NMHDR structure.
Return zero to continue the Undo operation.
Return a nonzero value to stop the Undo operation.
Minimum supported client
|Windows 2000 Professional [desktop apps only]|
Minimum supported server
|Windows 2000 Server [desktop apps only]|