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Topic review


Re: S3

I'm sending you an email with a development version of WinSCP to the address you have used to register on this forum.

Re: S3

Thanks for your post. This request has been added to the tracker:
Issue 572 – Amazon S3 protocol

Generally, I do not plan to add new protocol any time soon. Even FTP support is not mature enough. And there are so many file transfer protocol that WinSCP does not support yet.

Hello Martin,

I've made a (small) donation.

I was wondering if this would be sufficient for you to consider the idea and comment on your position.

Thanks, Bill

In the Login screen, we would have an additional "File protocol:" value 'S3'.

Protocol Options for 'S3' (i.e. appearing to the right of the "File protocol:") would be 'HTTP' and 'HTTPS'.

Host name might want to be

  • – Puts bucket names as top-level directories
  • <bucketname> – Provide access to a single named bucket

(I don't exactly know how S3 is structured, but I would guess that single-bucket names will cause requests to be sent directly to the servers of the S3 region (US / US-N.CA / Europe / AsiaPac) which the bucket is stored in, whereas using may cause requests to be routed via the US.)

Under protocol S3, the "User name:" label should be changed to "Access Key:" and the "Password:" label changed to "Secret Access Key".

"Port number:" should be defaulted to 80 or 443 based on the protocol options.

"Private key file" should be greyed-out.

I think "UTF-8 encoding for filenames" becomes irrelevant under S3, because the key names (effectively file names) are defined to be Unicode anyway (I think). (I think it will be URL percent escaping of UTF-8, but the point is that it is defined somewhere so there is no point having an option for it.)


It would be pretty handy if WinSCP supported AWS S3 as a back end.

S3 seems to just keep getting bigger and bigger.

There are various client softwares out there, for example:

  • S3Fox Organiser (<invalid hyperlink removed by admin>) – a plug-in for Firefox
  • s3cmd – a command-line tool implemented in Python

but so far I haven't found a decent Windows GUI program. In fact the omission is so obvious it makes me wonder if I have missed something...

I think if S3 support were added to WinSCP, it could scoop up a lot of users.

It would be nice if AWS would sponsor the implementation effort. But I think they make plenty of money out of being the storage back-end for various large websites.

But I assume you are making revenue from the third-party software pulled in from the WinSCP installer, so more users will mean more revenue in any case.