在Windows上，shutil.rmtree失败，显示“访问被拒绝”

Question

在Python中，当shutil.rmtree在包含只读文件的文件夹上运行时，将显示以下异常：

 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 216, in rmtree
   rmtree(fullname, ignore_errors, onerror)
 File "C:\Python26\lib\shutil.py", line 221, in rmtree
   onerror(os.remove, fullname, sys.exc_info())
 File "C:\Python26\lib\shutil.py", line 219, in rmtree
   os.remove(fullname)
WindowsError: [Error 5] Access is denied: 'build\\tcl\\tcl8.5\\msgs\\af.msg'

在“文件属性”对话框中查看时，我注意到该af.msg文件被设置为只读。

所以问题是：解决这个问题的 最简单的 解决方法/解决方案是什么-鉴于我的意图是rm -rf build/在Windows上做等效的事情？（无需使用诸如unxutils或cygwin之类的第三方工具-因为此代码的目标是在安装了Python2.6和PyWin32的裸机上运行）

Answer 1

检查以下问题：

python脚本在Windows中以什么用户身份运行？

显然，答案是将文件/文件夹更改为非只读，然后将其删除。

这是@Sridhar
Ratnakumar在评论中提到的onerror()处理程序pathutils.py：

def onerror(func, path, exc_info):
    """
    Error handler for ``shutil.rmtree``.

    If the error is due to an access error (read only file)
    it attempts to add write permission and then retries.

    If the error is for another reason it re-raises the error.

    Usage : ``shutil.rmtree(path, onerror=onerror)``
    """
    import stat
    if not os.access(path, os.W_OK):
        # Is the error an access error ?
        os.chmod(path, stat.S_IWUSR)
        func(path)
    else:
        raise