CURLOPT_HSTSWRITEDATA - Man Page

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HSTSWRITEDATA, void *pointer);

Data pointer to pass to the HSTS write function. If you use the CURLOPT_HSTSWRITEFUNCTION(3) option, this is the pointer you get as input in the fourth argument to the callback.

This option does not enable HSTS, you need to use CURLOPT_HSTS_CTRL(3) to do that.

NULL

This functionality affects http only

struct MyData {
  void *custom;
};

int main(void)
{
  CURL *curl = curl_easy_init();
  struct MyData this;
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");

    /* pass pointer that gets passed in to the
       CURLOPT_HSTSWRITEFUNCTION callback */
    curl_easy_setopt(curl, CURLOPT_HSTSWRITEDATA, &this);

    curl_easy_perform(curl);
  }
}

Added in curl 7.74.0

This returns CURLE_OK.

CURLOPT_HSTS(3), CURLOPT_HSTSREADDATA(3), CURLOPT_HSTSREADFUNCTION(3), CURLOPT_HSTSWRITEFUNCTION(3)

curl_easy_setopt(3), CURLOPT_HSTSREADDATA(3), CURLOPT_HSTSWRITEFUNCTION(3), libcurl-symbols(3).