evhttp returns notfound only

http_notfound.c

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <event.h>
#include <evhttp.h>

#define HTTPD_ADDR "0.0.0.0"
#define HTTPD_PORT 8080

void req_handler(struct evhttp_request *r, void *arg)
{
  evhttp_send_error(r, HTTP_NOTFOUND, "Not Found");
}

int main(int argc, const char* argv[])
{
  struct event_base *ev_base;
  struct evhttp *httpd;

  ev_base = event_base_new();

  httpd = evhttp_new(ev_base);
  if (evhttp_bind_socket(httpd, HTTPD_ADDR, HTTPD_PORT) < 0) {
    perror("evhttp_bind_socket()");
    exit(EXIT_FAILURE);
  }
  evhttp_set_gencb(httpd, req_handler, NULL);

  event_base_dispatch(ev_base);

  evhttp_free(httpd);
  event_base_free(ev_base);

  return 0;
}