Thanks Tamar!
Even for top level form the commands ? and ?? work exclusively if form.scrollbars=0 (not 1,2,3)
if form.scrollbars=0 the results are output on the form exactly as _screen (troncated).
this is a test (can change form.scrollbars in code).

Publi oform
oform=Newobject("asup")
oform.Show
Read Events
Retu
*
Define Class asup As Form
	Top = 75
	Left = 381
	Height = 303
	Width = 390
	ShowWindow = 2
	scrollbars=0     &&1,2,3 dont work !
	Caption = "Form1"
	Name = "form1"

	Add Object command1 As CommandButton With ;
		Top = 48, ;
		Left = 228, ;
		Height = 37, ;
		Width = 132, ;
		FontBold = .T., ;
		Caption = "? and ?? commands", ;
		MousePointer = 15, ;
		Name = "Command1"

	Procedure Destroy
	Clea Events
	Endproc

	Procedure command1.Click
	For i=1 To 500
		?i
		?? Cos(i)
	Endfor
	Endproc

Enddefine
*
*-- EndDefine: asup