Issue 1438480: shutil.move raises OSError when copystat fails (original) (raw)

Created on 2006-02-25 05:26 by piman, last changed 2022-04-11 14:56 by admin.

Files
File name Uploaded Description Edit
shutil.py.diff piman,2006-02-26 17:56 Fix copy2/copy
Messages (6)
msg27612 - (view) Author: Joe Wreschnig (piman) Date: 2006-02-25 05:26
If you are on a Linux system, and shutil.move a file from anywhere onto a partition where you have write permission but are not the owner, os.utime will fail with an EPERM OSError. This can (and did) happen moving a file on a vfat partition mounted with umask=0000, so every user had read/write/execute but all files were owned by root. This happens in shutil.copystat, so shutil.move doesn't remove the old file. The resulting error code (OSError, EPERM) is not distinguishable from several other permission errors that can happen during shutil.move, even though a failure to set a utime is not fatal for most move operations (mv(1) succeeds, for example). I would suggest either ignoring an EPERM from copystat, or catching it in shutil.copy2 and raising a more specific exception so that it can be easily distinguished from genuine failure due to permissions.
msg27613 - (view) Author: Joe Wreschnig (piman) Date: 2006-02-26 05:08
Logged In: YES user_id=796 The attached patch causes shutil.copy and shutil.copy2 (and so copytree, and move) to ignore EACCES and EPERM from copymode and copystat respectively. Other errors are reraised with the original traceback. Any error copying the file, rather than the metadata, is still considered fatal. User calls to copymode and copystat still fail as before. Justification: On Linux, utime(2) says the distinction between EACCES and EPERM is blurry and "Linux is not careful to distinguish between the EACCES and EPERM" so the patch ignores both. In my opinion, anyone wanting to deal with low-level details like mtimes and modes is probably not using shutil, so ignoring is better than a new exception (which would just result in complicated new code, and surprise old code). It's also easy for a caller to check if the mode/utimes were copied, if it's important to them.
msg27614 - (view) Author: Thomas Waldmann (thomaswaldmann) Date: 2007-03-24 18:51
See also http://sourceforge.net/tracker/index.php?func=detail&aid=1666318&group_id=5470&atid=105470 for a similar problem with copystat.
msg141827 - (view) Author: Éric Araujo (eric.araujo) * (Python committer) Date: 2011-08-09 15:36
> In my opinion, anyone wanting to deal with low-level details like > mtimes and modes is probably not using shutil As a moderately experienced UNIX user, I would say that file permissions are not low-level details. I see shutil functions as convenient wrappers to automate looping and calling a function, but I do care about file permissions. If people are still interested in this modification, I think it would need a backward-compatible change, for example in the form of a new argument ignore_permission_errors, or a more generic onerror callback like rmtree has.
msg221789 - (view) Author: Mark Lawrence (BreamoreBoy) * Date: 2014-06-28 14:05
The patch would need changing to allow for the follow_symlinks parameter and the backward compatibility issues mention in . Do we wait for an updated patch, close as "won't fix" or what?
msg358270 - (view) Author: Eshan Singhal (eshan-singhal) * Date: 2019-12-11 16:18
Amending shutil.copy and shutil.copy2 to expose a method of ignoring the permission errors rather than changing the current behaviour would not fix the original issue without further changes in consumers of these functions to pass through the new parameter (i.e. shutil.move in this scenario). This may be undesirable as copy_function is an optional parameter to shutil.move and so there would have to be a specialcase guard/check to see if the copy_function is shutil.copy or shutil.copy2 when passing in a new ignore_permission_errors parameter. I propose a new issue to track adding functionality to optionally ignore permission issues for shutil.copy/shutil.copy2, and this issue can remain open.
History
Date User Action Args
2022-04-11 14:56:15 admin set github: 42948
2021-12-26 15:58:26 ajaksu2 set keywords: - easyversions: + Python 3.9, Python 3.10, Python 3.11, - Python 3.3
2019-12-11 16🔞10 eshan-singhal set nosy: + eshan-singhalmessages: +
2019-06-02 07:38:22 Jeffrey.Kintscher set nosy: + Jeffrey.Kintscher
2019-03-16 00:01:19 BreamoreBoy set nosy: - BreamoreBoy
2014-06-28 14:05:35 BreamoreBoy set nosy: + BreamoreBoymessages: +
2011-08-09 15:36:21 eric.araujo set nosy: + eric.araujomessages: + versions: + Python 3.3, - Python 3.1, Python 2.7, Python 3.2
2010-08-26 16:38:07 BreamoreBoy set stage: test needed -> patch reviewversions: + Python 3.1, Python 2.7, Python 3.2, - Python 2.6, Python 3.0
2009-04-22 14:35:32 ajaksu2 set keywords: + easy
2009-03-21 00:36:36 ajaksu2 set keywords: + patchstage: test neededtype: behaviorversions: + Python 2.6, Python 3.0, - Python 2.4
2006-02-25 05:26:29 piman create