Re: [PATCH v4] http.c: use CURLOPT_RANGE for range requests

> A HTTP server is permitted to return a non-range response to a HTTP
> range request (and Apache httpd in fact does this in some cases).
> While libcurl knows how to correctly handle this (by skipping bytes
> before and after the requested range), it only turns on this handling
> if it is aware that a range request is being made.  By manually
> setting the range header instead of using CURLOPT_RANGE, we were
> hiding the fact that this was a range request from libcurl.  This
> could cause corruption.
> 
> Signed-off-by: David Turner <dturner@twopensource.com>
> ---
> 
> This one incorporates Jeff's suggestions about off_t.  It also
> simplifies by removing the possiblity of a missing low-end of a range;
> the entire point of this function is to add a range HEADER and a
> range of - is nugatory.