CURLOPT_RANGE.3: Caution against using it for HTTP PUT

AFAICT CURLOPT_RANGE does not support ranged HTTP PUT uploads so I've
cautioned against using it for that purpose and included a workaround.

Bug: https://curl.haxx.se/mail/lib-2019-04/0075.html
Reported-by: Christopher Head
Closes https://github.com/curl/curl/issues/3814

diff --git a/docs/libcurl/opts/CURLOPT_RANGE.3 b/docs/libcurl/opts/CURLOPT_RANGE.3
index e90696c01a76e4f876c5b8c5ff40a56c28843610..02ac2762bc126ecbf1108dd8d404830b54ae41fc 100644 (file)
--- a/docs/libcurl/opts/CURLOPT_RANGE.3
+++ b/docs/libcurl/opts/CURLOPT_RANGE.3
@@ -43,6 +43,14 @@ For RTSP, the formatting of a range should follow RFC2326 Section 12.29. For
 RTSP, byte ranges are \fBnot\fP permitted. Instead, ranges should be given in
 npt, utc, or smpte formats.
 
+For HTTP PUT uploads this option should not be used, since it may conflict with
+other options. If you need to upload arbitrary parts of a file (like for
+Amazon's web services) support is limited. We suggest set resume position using
+\fICURLOPT_RESUME_FROM(3)\fP, set end (resume+size) position using
+\fICURLOPT_INFILESIZE(3)\fP and seek to the resume position before initiating
+the transfer for each part. For more information refer to
+https://curl.haxx.se/mail/lib-2019-05/0012.html
+
 Pass a NULL to this option to disable the use of ranges.
 
 The application does not have to keep the string around after setting this