curl / Mailing Lists / curl-library / Single Mail
Buy commercial curl support. We help you work out your issues, debug your libcurl applications, use the API, port to new platforms, add new features and more. With a team lead by the curl founder Daniel himself.

When CURLOPT_RANGE is specified in the FTP protocol, does it ever write out-of-range data?

From: Yoshimasa Ohno via curl-library <curl-library_at_lists.haxx.se>
Date: Thu, 7 Aug 2025 21:52:59 +0900

Hello everyone.

I am developing an application with FTP client functionality using libcurl.

In the application, I am trying to specify the retrieval range in
CURLOPT_RANGE and write
incoming data through CURLOPT_WRITEFUNCTION.

As far as I can tell, the callback to CURLOPT_WRITEFUNCTION doesn't seem to
pass over data outside the range specified by
CURLOPT_RANGE. Is this a coincidence? Or is it designed that way?

The CURLOPT_RANGE documentation states that the range specification may be
ignored by the HTTP protocol.
Since the FTP protocol does not have a range specification (end-of-range
specification) mechanism, we expect that the libcurl side is designed to
ignore out-of-range data.

What do you think?


-- 
Unsubscribe: https://lists.haxx.se/mailman/listinfo/curl-library
Etiquette:   https://curl.se/mail/etiquette.html
Received on 2025-08-07