Splitpane behaviour on size change

wSplitSetSizeChangeStyle
This macro changes the behaviour of a WC_SPLITPANE on size change.
Syntax:
BOOL wSplitSetSizeChangeStyle(HWND hwnd, ULONG flag);
Parameters:
HWND hwnd:splitpane window handle.
ULONG flag:SPLITS_PROPORTIONAL the size rate of the two panes is fixed,
SPLITS_FIXED1 keep the size of the left/top pane,
SPLITS_FIXED2 keep the size of the right/bottom pane.
Return value:
BOOL:TRUE if the operation was successful,
FALSE in case of error.
Example:
rc = wSplitSetSizeChangeStyle(hwndSplitPane, SPLITS_FIXED1); ...

dSplitSetSizeChangeStyle
This macro changes the behaviour of a WC_SPLITPANE on size change.
Syntax:
BOOL dSplitSetSizeChangeStyle(HWND hwndDlg, ULONG id, ULONG flag);
Parameters:
HWND hwndDlg:dialog window handle.
ULONG id:splitpane window ID.
ULONG flag:SPLITS_PROPORTIONAL the size rate of the two panes is fixed,
SPLITS_FIXED1 keep the size of the left/top pane,
SPLITS_FIXED2 keep the size of the right/bottom pane.
Return value:
BOOL:TRUE if the operation was successful,
FALSE in case of error.
Example:
rc = dSplitSetSizeChangeStyle(hwndDlg, ID_SPLITPANE, SPLITS_FIXED1); ...