LDown
Simulates a press of the left mouse button. This is like pressing the mouse button down but not releasing it. It is half of a click.
Issuing this command and then using MouseMove would implement dragging. Use LUp to complete the operation.
Abbreviation : LDo
See also: LClick, LUp, LDblClick, RClick, RDown, RUp, RDblClick, MDown, MUp, MDblClick, MClick, MouseMove, MouseMoveRel, MouseOver