Rate limit

Lets an application set a speed cap. Do not transfer data faster than a set number of bytes per second. libcurl then attempts to keep the average speed below the given threshold over a period of multiple seconds.

There are separate options for receiving (CURLOPT_MAX_RECV_SPEED_LARGE) and sending (CURLOPT_MAX_SEND_SPEED_LARGE).

Here is an example source code showing it in use:

#include <stdio.h>
#include <curl/curl.h>

int main(void)
  CURL *curl;
  CURLcode res = CURLE_OK;

  curl = curl_easy_init();
  if(curl) {
    curl_off_t maxrecv = 31415;
    curl_off_t maxsend = 67954;

    curl_easy_setopt(curl, CURLOPT_MAX_RECV_SPEED_LARGE, maxrecv);
    curl_easy_setopt(curl, CURLOPT_MAX_SEND_SPEED_LARGE, maxsend);

    curl_easy_setopt(curl, CURLOPT_URL, "https://curl.se/");

    res = curl_easy_perform(curl);


  return (int)res;