python / python/cpython

shutil's move function fails to handle files opened by another process

未关闭
#120,882 0 条评论 2 个 reaction 已指派 0 人 在 GitHub 查看

还没有人认领这个 Issue。

OS-windows type-bug
主要语言
Python
星标
77.2k
派生
35.9k
PR 合并指标
PR 指标待抓取

描述

Bug report

Bug description:

Problem:

When attempting to move a file using shutil.move from one location to another, if the file is opened by another process (if file is opened in other python script using open function), shutil.move raises an error (WinError 32: The process cannot access the file because it is being used by another process). Despite this error, the file is still copied to the destination directory, which is unexpected behavior.

Details:

The shutil.move function is designed to handle moving files or directories between locations. However, it does not check if the file is currently open by another process before attempting to move it. This results in an error being raised, but the file is still copied to destination regardless of the error condition.

Solution:

To address this issue, I modified the shutil.move function to include an additional check for OSError with errno.EACCES (Permission Denied) in the exception handling block. This ensures that if the file cannot be moved due to being opened by another process, the operation is aborted cleanly without copying the file to maintain the integrity of the move function as well as file system.

Here is the modified part of the shutil.move function

    except OSError as exc:
        if exc.errno == errno.EACCES:
            raise  # Propagate the PermissionError
     # Existing code

Proposal:

I propose adding this error handling improvement to the shutil.move function in Python's standard library. This enhancement will make file operations more reliable in scenarios where files may be concurrently accessed by multiple processes

Steps to Reproduce:

  • Open a file (test.pdf) in any python script using open function in read mode.
  • Attempt to move the file using shutil.move to another directory.
  • Observe the WinError 32 exception and incorrect copying behavior.
  • Close the file (To avoid memory leakage).

NOTE: Avoid to use context manager here for opening file to find the error.
You can also run the following script to get the error.

import shutil

src = "C://Users//Desktop//Downloads//test.pdf" # Provide full file path of your system.
dst_dir = "D://Files" # Provide destination directory path.
f = open(src, "r")
try:
    shutil.move(src, dst_dir)
except Exception as e:
    print(e)
finally:
    f.close()

Expected Behavior:

When shutil.move encounters a situation where the source file is open in another process (WinError 32), it should raise an exception and abort the operation without performing any partial file copying to the destination.

Impact:

This issue affects users trying to use shutil.move to relocate files that are concurrently accessed by other processes. The proposed solution aims to improve the robustness and expected behavior of the function in such scenarios.

CPython versions tested on:

3.10

Operating systems tested on:

Windows

Linked PRs
  • gh-120883

贡献指南

打开贡献指南

从这里开始

  1. 先读完整个 Issue,再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库,在一个分支上完成修改。
  4. 提交 Pull Request,并在描述里引用这个 Issue 编号。

调研方向

从 shutil.move 入口开始,使用被另一个进程保持打开状态的源文件复现报告的 Windows 行为。验证该操作会引发预期的异常,且不会留下复制出的目标文件,并在开始之前检查相关联的 PR gh-120883,因为该 issue 已经有相关工作。

由索引模型根据 Issue 内容生成。

评估

技术栈
python
领域
operating-systems
Issue 类型
缺陷
难度
3/5
预计耗时
1-2 天
活跃度
停滞
描述清晰度
基本清楚
新手友好度
25/100

把新 issue 发到你的邮箱

精选适合新手参与的 GitHub issue 摘要。