BCGControlBar Pro for MFC
UINT BCGM_ON_RENAME_TAB

The message is sent to the parent of tabbed window when the user has renamed a tab using in-place editing.

Parameters
wParamcontains the zero-based index of a tab whose name has been changed.
lParama pointer to string that contains a new tab name.
Returns
application should return nonzero if it processes this message and CBCGPBaseTabWnd::SetTabLabel should NOT be called.

You should process this message to receive notifications from tabbed windows when a tab name is changed. If you do not process this message or return zero, the default implementation calls CBCGPBaseTabWnd::SetTabLabel with the name specified by user while editing.