text: 
  #include <pthread.h>
  #include <errno.h>
  
  pthread_mutex_t mutex;
  
  int __VERIFIER_atomic_begin()
  {
      pthread_mutex_lock(&mutex);
      return 0;
  }
  
  int __VERIFIER_atomic_end()
  {
      pthread_mutex_unlock(&mutex);
      return 0;
  }
  