CURLOPT_RESUME_FROM − set a point to resume transfer from
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_RESUME_FROM, long from);
Pass a long as parameter. It contains the offset in number of bytes that you want the transfer to start from. Set this option to 0 to make the transfer start from the beginning (effectively disabling resume). For FTP, set this option to -1 to make the transfer start from the end of the target file (useful to continue an interrupted upload).
When doing uploads with FTP, the resume position is where in the local/source file libcurl should try to resume the upload from and it will then append the source file to the remote target file.
If you need to resume a transfer beyond the 2GB limit, use CURLOPT_RESUME_FROM_LARGE(3) instead.
0, not used
HTTP, FTP, SFTP, FILE
CURL *curl =
curl_easy_setopt(curl, CURLOPT_URL, "ftp://example.com");
upload at byte index 200 */
curl_easy_setopt(curl, CURLOPT_RESUME_FROM, 200L);
/* ask for
curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
/* set total
data amount to expect */
curl_easy_setopt(curl, CURLOPT_INFILESIZE, size_of_file);
/* Perform the
CURLOPT_RESUME_FROM_LARGE(3), CURLOPT_RANGE(3), CURLOPT_INFILESIZE(3),