C - 指针与 integer（'char *' 和 'int'）之间的比较

Question

I'm very new at C and I'm having a problem using function strstr . Make gives me a warning that I do not understand, anybody can explain?

warning: comparison between pointer and integer ( char * and int ) if (strstr(reference, number_start) == 1) warning generated.

My code:

#include <stdio.h>
#include <string.h>


int main (void) {
    char reference[]        = "34,37";
    char number[]           = "34567890123456";
    char number_start[]     = {number[0], number[1], '\0'};

    if (strstr(reference, number_start) == 1) {
        printf("Yup, iit's workin'\n");
    } else {
        printf("Try again, wookie\n");
    }

    return 0;
}

Answer 1

strstr() return a pointer to the first substring if found, and NULL if not found.

Replace

if (strstr(reference, number_start) == 1) {

with

if (strstr(reference, number_start) != NULL) {

to check if number_start is in reference .

Answer 2

Do int(strstr(a,b)) if strstr is not null for index.