new file:   bin/signal
	new file:   clearbin.sh
	modified:   mvbin.sh
	new file:   prog10_1.c
	new file:   prog10_18.c
	new file:   prog10_19.c
	new file:   prog10_2.c
	new file:   prog10_20.c
	new file:   prog10_3.c
	new file:   prog10_4.c
	new file:   prog10_5.c
	new file:   prog10_7.c
	new file:   signal.c
	new file:   temp.foo