> For the complete documentation index, see [llms.txt](https://xiaoxiami.gitbook.io/linux-server/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://xiaoxiami.gitbook.io/linux-server/wen-jian-cao-zuo.md).

# 文件I/O

这里的介绍文件操作，

* 一种是基于文件描述符的I/O操作。(由Linux内核操作管理文件)
* 一种是基于流的I/O操作。（流I/O是由C语言的标准函数库提供的，因此也称为标准I/O）

如图各自所在的层

![](/files/-LfnTJH3GU6I2ndJLZwu)

C语言的标准库，在用户空间，基于流的标准I/O：流和FILE对象。

linux底层系统调用，在内核空间，基于文件描述符的底层系统调用I/O。


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