man fflush 一下，有下面这个说法：
For input streams associated with seekable files (e.g., disk files, but not pipes or terminals), fflush() discards any buffered data that has been fetched from the underlying file, but has not been consumed by the application.
但也还是不理解“has not been consumed by the application”这句。

【 在 kirbyzhou 的大作中提到: 】
: fflush ??
: 你不是只读的打开的么？
:
--
FROM 119.143.221.*