c - 如果fclose()失败，文件描述符是否仍然打开？

Question

想象下面的代码作为线程运行:

void *thread_worker(void *q) {
 for (;;) {
  int fd = some_queue_get(q);
  FILE *writer = fdopen(fd, "w");
  if (!writer) { perror("fdopen"; close(fd); continue; }
  // do something with writer

  if (fclose(writer) == EOF) {
   perror("fclose writer");
   // should fd be closed here?
   close(fd);
  }
}

fclose(3)可能由于各种原因而失败-是否可以保证/当底层文件描述符关闭时或之后仍然打开？

如果在刷新失败时未通过fclose关闭fd，则会泄漏fds而不会进行其他关闭。

如果fd由fclose关闭，则额外的关闭可能会关闭由另一个线程新打开的文件描述符。

Answer 1

man fclose也不提供我系统上的答案，但是man 3p fclose揭示了official version from the POSIX Programmer's manual，它在此问题上更加全面:

The fclose() function shall perform the equivalent of a close() on the file descriptor that is associated with the stream pointed to by stream.