Eryk Sun added the comment:
If you own the only reference you can also delete the reference, which
deallocates the iterator and closes the handle.
Can you provide concrete examples where os.remove and os.chmod fail? At least
in Windows 7 and 10 the directory handle is opened with the normal read and
write sharing, but also with delete sharing. This sharing mode is fairly close
to POSIX behavior (an important distinction is noted below). I get the
following results in Windows 10:
>>> import os, stat
>>> os.mkdir('test')
>>> f = open('test/file1', 'w'); f.close()
>>> f = open('test/file2', 'w'); f.close()
>>> it = os.scandir('test')
>>> next(it)
<DirEntry 'file1'>
rename, chmod, and rmdir operations succeed:
>>> os.rename('test', 'spam')
>>> os.chmod('spam', stat.S_IREAD)
>>> os.chmod('spam', stat.S_IWRITE)
>>> os.remove('spam/file1')
>>> os.remove('spam/file2')
>>> os.rmdir('spam')
Apparently cached entries can be an issue, but this caching is up to WinAPI
FindNextFile and the system call NtQueryDirectoryFile:
>>> next(it)
<DirEntry 'file2'>
An important distinction is that a deleted file in Windows doesn't actually get
unlinked until all handles and kernel pointer references are closed. Also, once
the delete disposition is set, no *new* handles can be created for the existing
file or directory (all access is denied), and a new file or directory with same
name cannot be created.
>>> os.listdir('spam')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
PermissionError: [WinError 5] Access is denied: 'spam'
>>> f = open('spam', 'w')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
PermissionError: [Errno 13] Permission denied: 'spam'
If we had another handle we could use that to rename "spam" to get it out of
the way, at least. Without that, AFAIK, all we can do is deallocate the
iterator or wait for it to be exhausted, which closes the handle and thus
allows Windows to finally unlink "spam":
>>> next(it)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
StopIteration
Creating a new file named "spam" is allowed now:
>>> f = open('spam', 'w')
>>> f.close()
----------
nosy: +eryksun
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<http://bugs.python.org/issue26111>
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