The TCM_GETROWCOUNT message retrieves the current number of rows of tabs in a tab control. You can send this message explicitly or by using the TabCtrl_GetRowCount macro.
TCM_GETROWCOUNT
wParam = 0; // not used; must be zero
lParam = 0; // not used; must be zero
Return Values
Returns the number of rows of tabs.
Remarks
Only tab controls that have the TCS_MULTILINE style can have multiple rows of tabs.
See Also