> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/man/man9/vop_strategy.9.md).

# VOP\_STRATEGY.9

`VOP_STRATEGY` — 读取或写入文件系统缓冲区

## 名称

`VOP_STRATEGY`

## 概要

```c
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/vnode.h>
```

```c
int
VOP_STRATEGY(struct vnode *vp, struct buf *bp)
```

## 描述

参数如下：

**`vp`** 缓冲区对应的 vnode。

**`bp`** 要读取或写入的缓冲区。

此调用根据 `bp->b_iocmd` 的值从文件中读取或写入数据。

此调用可能会阻塞。

## 返回值

始终返回零。错误应通过在 `bp->b_ioflags` 中设置 `BIO_ERROR` 位并将 `bp->b_error` 设置为适当的 `errno` 值来表示。

## 参见

[errno(2)](https://github.com/FreeBSD-Ask/freebsd-man-sc/tree/main/man2/errno.2.md), [buf(9)](/man/man9/buf.9.md), [vnode(9)](/man/man9/vnode.9.md)

## 作者

本手册页面由 Doug Rabson 编写。


---

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