a single or double cylinder circular knitting machine is adapted to effect renewal of a needle selection at one or more successive yarn feeds without requiring a respective pattern selection device therefor . the pattern jacks which have been selected , by a preceding pattern selection device , not to bring their respective needles to knit are moved radially inwards by a guiding cam , and are held separated from the other jacks even after the latter have brought their respective needles to knit . the cam may have a first movable part and a second fixed part . at one position of the movable part , the inoperative jacks are moved radially to the inside of the fixed part , and at the second position thereof , radially to the outside thereof , thereby they are restored to the selection position . this allows operation with a programmed selection even where the selection was formerly just reiterated .