C/string.h/strcoll

//Declaration:  int strcoll(const char *str1, const char *str2);
//Return:       returns an integer that is interpreted as follows:
                <0      str1 is less than str2
                0       str1 is equal to str2
                >0      str1 is greater than str2

#include<stdio.h>
#include<string.h>
int main(void){
    if(strcoll("hi", "hi")) {
       printf("Equal");
    }
}