test5.c

#include "uthash.h"
#include <stdlib.h>   /* malloc */
#include <stdio.h>    /* printf */

typedef struct example_user_t {
    int id;
    int cookie;
    UT_hash_handle hh;
    UT_hash_handle alth;
} example_user_t;

int main()
{
    int i,j;
    example_user_t *user, *tmp, *users=NULL, *altusers=NULL;

    /* create elements */
    for(i=0; i<10; i++) {
        user = (example_user_t*)malloc(sizeof(example_user_t));
        if (user == NULL) {
            exit(-1);
        }
        user->id = i;
        user->cookie = i*i;
        HASH_ADD_INT(users,id,user);
        HASH_ADD(alth,altusers,cookie,sizeof(int),user);
    }

    /* find cookie corresponding to each even ID */
    for(i=0; i<10; i+=2) {
        j=i*i;
        HASH_FIND(alth,altusers,&j,sizeof(int),tmp);
        if (tmp != NULL) {
            printf("cookie %d found, user id %d\n", tmp->cookie, tmp->id);
        } else {
            printf("cookie %d not found\n", j);
        }
    }
    return 0;
}