- From: Scott Penrose <scottp@dd.com.au>
- Date: Wed, 9 Nov 2011 13:59:46 +1100
- To: Karl Dubost <karld@opera.com>
- Cc: Brolin Empey <brolin@brolin.be>, "www-tag@w3.org List" <www-tag@w3.org>
> > Le 4 nov. 2011 à 19:18, Brolin Empey a écrit : >> The Web browser should preserve the file system last modified time by default because this time cannot easily be recovered after it is discarded. I have been thinking about this over the last week and which way it should happen. It is interesting to note that many older backup systems use last modified as a method to work out if files need incremental backup. The problem is that once you download a file, they are not linked. The file on your system does not match the remote system. So what does modified mean? Lets put 3 systems into play. * Server1 - file.png, last modified 2010-01-01 * Server 2 - file.png downloaded, last modified 2010-01-01 * Client 1 - Download file from Server 2, use if mod since Scenario 1 - Server 2 modifies the PNG (maybe a resize). Last modified should change to that day (2011-10-01), Client can download. Scenario 2 - Server 1 had updated the logo in 2011-06-01; now Server 2 downloads from Server 1, preserving date modified as 2011-06-01; Client now checks if file has changed since last of 2011-10-01 - it has changed, but now client won't get it. On the other hand, if Server 2 had set last modified to today 2011-11-09 - it would not be an issue. Scenario 3 - A client downloads a file to Download folder, has a look at recent files. User would expect to see newest files downloaded with todays date. I don't think HTTP Clients should preserve modified date time. But there are exceptions - e.g. WebDAV / SVN over HTTP. Scott
Received on Wednesday, 9 November 2011 03:00:19 UTC