.literalXDIR Design MethodologyAThe design of XDIR follows the design of sample routine XGFUNC. +DIRUSE has 5 modes which are defined below. Mode definitions:= 1) Call DIRINP and set up the constraints for module XXSCON.E Set flag IFGSET to zero indicating not to call XXGSET for general variables. 2) Initialize a sequence.7 3) Process a sequence. (does it meet the constraints?) 4) End of sequence. 5) End of task..el