SDK esp32 with SNTP

General
1

I have this code but don’t work, I thinking ESP_ERROR_CHECK(esp_netif_init()); inside in SDK does not linker full. someone its has one example of SNTP?

/**
 time_ntp.c
Módulo de sincronización de hora vía SNTP
 */
#include <string.h>
#include <time.h>
#include <sys/time.h>
#include "esp_system.h"
#include "esp_log.h"
#include "esp_netif_sntp.h"
#include "esp_sntp.h"

/* ========= CONFIGURACIÓN ========= */
#define SNTP_MAX_RETRY 5            // reintentos máximos
#define SNTP_BACKOFF_BASE_MS 1000   // 1s exponencial
#define NTP_RESYNC_INTERVAL_HOURS 1 // resincronización automática cada N horas
#define DEFAULT_TZ "EST5"           // Bogotá (-5 sin DST)

/* ========= ESTADO ========= */
static const char *TAG = "SNTP";
static bool s_time_synced = false;

/* ========= CALLBACK ========= */
static void SNTP_TimeSyncCallback(struct timeval *tv)
{
    s_time_synced = true;
    time_t now;
    struct tm timeinfo;
    char buf[64];

    time(&now);
    gmtime_r(&now, &timeinfo);
    strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%SZ", &timeinfo);
    ESP_LOGI(TAG, "Tiempo sincronizado: %s (UTC)", buf);
}
/* ========= API ========= */
void time_ntp_init(void)
{
    ESP_LOGI(TAG, "Inicializando SNTP...");
    esp_sntp_config_t config = ESP_NETIF_SNTP_DEFAULT_CONFIG_MULTIPLE(
        3,
        ESP_SNTP_SERVER_LIST("pool.ntp.org", "co.pool.ntp.org", "south-america.pool.ntp.org"));

    config.sync_cb = SNTP_TimeSyncCallback;
    config.smooth_sync = true;
    esp_netif_sntp_init(&config);

    // Configura resincronización automática
    esp_sntp_set_sync_interval(NTP_RESYNC_INTERVAL_HOURS * 3600 * 1000);

    // Zona horaria global
    setenv("TZ", DEFAULT_TZ, 1);
    tzset();
}

bool time_ntp_wait_for_sync(void)
{
    int retry = 0;

    while (!s_time_synced && retry < SNTP_MAX_RETRY)
    {
        int backoff = SNTP_BACKOFF_BASE_MS << retry;
        ESP_LOGW(TAG, "Esperando sincronización... intento %d/%d (espera %d ms)", retry + 1, SNTP_MAX_RETRY, backoff);
        vTaskDelay(pdMS_TO_TICKS(backoff));
        retry++;
    }
    return s_time_synced;
}

bool time_ntp_is_synced(void)
{
    return s_time_synced;
}

void time_ntp_print(void)
{
    time_t now;
    struct tm timeinfo;
    char buf[64];
    time(&now);
    // UTC
    gmtime_r(&now, &timeinfo);
    strftime(buf, sizeof(buf), "%Y-%m-%dT%H:%M:%SZ", &timeinfo);
    ESP_LOGI(TAG, "UTC: %s", buf);
    // Local
    localtime_r(&now, &timeinfo);
    strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S (%Z)", &timeinfo);
    ESP_LOGI(TAG, "Local: %s", buf);
}

/* ========= TASK ========= */
void time_ntp_task(void *pvParameters)
{
    time_ntp_init();
    if (!time_ntp_wait_for_sync())
    {
        ESP_LOGE(TAG, "No se pudo sincronizar con servidores NTP");
        vTaskDelete(NULL);
    }
    // Loop infinito: imprime cada 10s
    while (1)
    {
        time_ntp_print();
        vTaskDelay(pdMS_TO_TICKS(10000)); // cada 10s
    }
}