A search operation may be initiated either by the application (see TXC.SRCHKEY) or by the user by clicking on the search icon (binoculars) on the toolbar (see TXF_TOOLBAR and TXC.TOOLBARMASK) or by hitting F5 (assuming that TXC.FMAPCTL has been set to forward F5 to the control. The operator can continue searching for additional matches by hitting Ctrl+F (search forwards) or Ctrl+Shift+F (search backwards)..
Currently replace operations can only be initiated by the user, by hitting F6 (again, assuming that that TXC.FMAPCTL has been set to forward F6 to the control).