Function helper

examples/interrupt.c:26–35

#include <time.h>

static void *helper(void *_engine) {
  wasm_engine_t *engine = _engine;
  struct timespec sleep_dur;
  sleep_dur.tv_sec = 1;
  sleep_dur.tv_nsec = 0;
  nanosleep(&sleep_dur, NULL);
  printf("Sending an interrupt\n");
  wasmtime_engine_increment_epoch(engine);
  return 0;
}

static void spawn_interrupt(wasm_engine_t *engine) {
  pthread_t child;