digraph functiondeps {

	node [
		style = filled
		shape = "record"
		fillcolor = "lightskyblue"
	];

	"main" [
		label = "{ <fi> | main | <fo> }"
	];
	"main":fo -> "atoi":fi;
	"main":fo -> "printf":fi;
		"atoi" [
			label = "{ <fi> | atoi | <fo> }"
			fillcolor = "red"
		];
		"printf" [
			label = "{ <fi> | printf | <fo> }"
			fillcolor = "red"
		];
}