to_digit          623 kern/subr_prf.c #define is_digit(c)	((unsigned)to_digit(c) <= 9)
to_digit          839 kern/subr_prf.c 				n = 10 * n + to_digit(ch);
to_digit          856 kern/subr_prf.c 				n = 10 * n + to_digit(ch);