CURLOPT_RESUME_FROM(3) Introduction to Library Functions

NAME

CURLOPT_RESUME_FROM - offset to resume transfer from

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_RESUME_FROM, long from);

DESCRIPTION

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
then appends 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.

DEFAULT

0, not used

PROTOCOLS

This functionality affects all supported protocols

EXAMPLE

int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
long size_of_file;

curl_easy_setopt(curl, CURLOPT_URL, "ftp://example.com");

/* resume upload at byte index 200 */
curl_easy_setopt(curl, CURLOPT_RESUME_FROM, 200L);

/* ask for upload */
curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

/* set total data amount to expect */
curl_easy_setopt(curl, CURLOPT_INFILESIZE, size_of_file);

/* Perform the request */
curl_easy_perform(curl);
}
}

AVAILABILITY

Added in curl 7.1

RETURN VALUE

curl_easy_setopt(3) returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non-zero means an error
occurred, see libcurl-errors(3).

SEE ALSO

CURLOPT_INFILESIZE(3), CURLOPT_RANGE(3), CURLOPT_RESUME_FROM_LARGE(3)

libcurl 2025-02-25 CURLOPT_RESUME_FROM(3)