to_digit          102 usr/lib/libc/stdio/vfprintf.c #define is_digit(c)	((unsigned)to_digit(c) <= 9)
to_digit          337 usr/lib/libc/stdio/vfprintf.c 				n = 10 * n + to_digit(ch);
to_digit          354 usr/lib/libc/stdio/vfprintf.c 				n = 10 * n + to_digit(ch);