site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com Le 26 juin 08 à 15:29, Chris a écrit : <http://bugreport.apple.com> Thanks, -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/tlambert%40apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... On Jun 26, 2008, at 3:54 PM, Chris wrote: On 27/06/2008, at 3:51 AM, Terry Lambert wrote: On Jun 26, 2008, at 7:02 AM, Chris <idou747@gmail.com> wrote: On 26/06/2008, at 11:46 PM, Jean-Daniel Dupas wrote: I was looking for a way to figure out how long files have been in the trash, and I was hoping that stat.st_ctimespec would provide that, seeing as stat(2) says that rename(2) and link(2) will update the ctime. However this isn't the case. Renaming files doesn't affect the ctime. Is this because Darwin doesn't implement ctime, or because HFS+ doesn't implement it, or am I missing something else? Or because moving a file on HFS+ is not considere as renaming it ? On HFS+, the file name is just an other metadata (like ctime) and is not formely part of the path. Moving a file in HFS+ is just changing its parent, not its name. ctime on unix has nothing really to do with the path either, but rather the inode. Even on HFS, making another link to the file will update the ctime. In fact that is an old fashioned way of renaming on unix - link to the new path and unlink the old path (which temporarily changed the inode link count). Since BSD unix, rename is now done in the kernel rather than link/unlink, but it is still considered an event that is supposed to update the ctime. Incorrect; POSIX states that the st_ctime and st_mtime of the directory that the file was renamed from/to shall be marked for update. The file itself is unchanged by the operation; it has no idea that it has been renamed. Even if POSIX is silent about ctime for the file, the Mac-OSX documentation for stat(2) is not silent, and says that the ctime should be updated. Also, all the UNIXes that I am aware of will update the ctime for rename. The documentation is wrong and the specification and current implementation is correct. Please file a bug report so that we can update the documentation. You could maybe stretch an implementation detail of HFS and claim that the btree linkages for the catalog node have been changed, and that therefore directory mtime has been changed, but that will likely not fly very far. I think its fair to say that all talk of btrees, cagalogs and other implementation details aren't really relevant to the discussion of what an API should do. You don't change an API just because some implementation detail is different. The directory ctime argument for its update on a directory change is actually predicated on another assumption that might not be valid, based on the implementation detail that "directories are files, and changing directory data is therefore changing file contents". This was true for UFS, but is not true on btree-based directories in HFS or other FSs with different implementation details. POSIX should probably update the standard to only mtime being "shall be marked for update", and ctime "may be marked for update", but it's not costing us more than a flag compare and an assignment to do both. I don't see that the cost is the primary consideration in formulating standards. All the meta-data imposes cost, but we have it because it is useful. In this case, ctime is remarkably irrelevant if rename doesn't update it. This email sent to tlambert@apple.com This email sent to site_archiver@lists.apple.com