isdigit - Test for digit

Definition	#include <ctype.h> int isdigit(int c); isdigit checks whether the character c is a digit (0-9).
Return val.	!= 0 0	c is a digit. c is not a digit.
Note	isdigit is implemented both as a macro and as a function (see section “Functions and macros”).
Example	#include <ctype.h> #include <stdio.h> int main(void) { int c; while((c = getchar()) != EOF) printf("%s : %c\n", ((isdigit(c)) ? "Digit" : "Other"), c); return 0; }
See also	isalnum, isascii, iscntrl, isalpha, isgraph, islower, isprint, ispunct, isspace, isupper, isxdigit, isebcdic, iswdigit