Possible to copy/overwrite only when size is different?

[bucke...@gmail.com]

Hello,

I'm using Amazon Drive (slow, but cheap and unlimited storage) with Netdrive as my backup solution, and FastCopy is an excellent utility to just copy my data onto the Amazon Drive. There is only one big problem, it isn't possible to copy the DATE attribute with my files. This means that for all files the DATE attribute is set to the time the file was copied to the cloud, and not the time it was actually created on my end. Sadly, this also means that when I try to use FastCopy with Sync(Size/Date) that it wants to copy every single file again, even those that are exactly the same (except for the DATE attribute, of course) between Amazon Drive and my local copy.  

So I'm basically looking for a way to just Sync(Size).  Ignoring Date, but copying every file from Source to DestDir that has a different size and deleting everything on DestDir that isn't present on Source.   
Is this possible with FastCopy?  

[Hiroaki SHIROUZU]

Sorry, FastCopy's Sync mode can be used for your purpose.

It seems Amazon drive doesn't keep modification timestamp.

If Amazon drive keeps creation timestamp, add

 default_copy_flags="32768"

to [main] section in fastcopy2.ini.

(this value means "creation timestamp")

If Amazon drive doesn't keep modification timestamp, but also creation timestamp, I have no solution.

[bucke...@gmail.com]

Thank you for your quick answer.

Sadly, the ini modification did not help because Amazon does not keep any timestamp for files. Amazon seems to always set the creation and modification timestamp to the date the file was uploaded.  
But I found a workaround:  

1. upload all files first with FastCopy because it is fast and reliable.
2. use robocopy for maintenance later when synchronizing between local files and Amazon.

Thanks again :)

[Hiroaki SHIROUZU]

It was good.

Robocopy uses archive bit for discrimination updated files?

[bucke...@gmail.com]

robocopy has a mirror parameter that compares all files and directories on the Amazon drive with my local files. Together with /XN (exclude newer files) and /XO (exclude older files) robocopy will simply ignore all date attributes and just copy files that have a different size; this includes files that are not already present on the Amazon drive. And with /mir it also deletes all files from the Amazon drive that are no longer present on my local drive.  
For example this command synchronizes the Amazon drive with my local data:

robocopy n:\Film\Japan\Movies\ w:\Videos\Film\Japan\Movies\ *.* /e /mir /XN /XO /log:robocopy.log

(n: is my local drive and w: is the Amazon drive)

But robocopy it is really slow when compared to FastCopy.

[goo...@tradetimer.com]

Would seting the "Tolerance at the timestamp" (Copy/Move Options in Settings) to some huge number, and then using "Sync (Size/Date)" method do what you need? I use 3602000 msec to disregard 'one hour and two second' differences. Perhaps 3153600000 (32-billion) for a year? I'm not sure FastCopy can handle such a large number. If not, can you can get by with less than a year difference?

I have lots of files that are the same size but with different contents, so date and time is critical for me. Too bad Amazon messes with the timestamps. Do they have a setting somewhere that will keep that from happening?

[Thomas Buckermann]

If not, can you can get by with less than a year difference?

Sadly not in this case. Some of my local files are much older than one year. And in the specific case for these movie files, all "Modified" attributes are set to the date the movie was released. Which means some files were "modified" almost 100 years ago ;)

Too bad Amazon messes with the timestamps. Do they have a setting somewhere that will keep that from happening?

No, sadly there is no setting for this. The created/modified attribute is always set to the moment the file was uploaded to the Amazon drive. And just to be sure I tried a few different programs which can uploads to Amazon drive, including through the web interface. But the result is always the same, date attributes are set to the current date/time.
For example this file was uploaded on the 22.May and I guess the upload took around 12 minutes.
 

Google Drive, on the other hand, preserves these attributes. But it would be MUCH more expensive than the yearly 70€, for the slow and uncomfortable but unlimited storage, Amazon Drive costs.

But honestly, I'm not really complaining. Though a bit unwieldy, and I would prefer to exclusively use FastCopy, it works for me with combination of FastCopy/robocopy.