CURLOPT_HSTSREADDATA(3) - Man pages

CURLOPT_HSTSREADDATA(3)     Library Functions Manual    CURLOPT_HSTSREADDATA(3)

NAME
       CURLOPT_HSTSREADDATA - pointer passed to the HSTS read callback

SYNOPSIS
       #include <curl/curl.h>

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

DESCRIPTION
       Data  pointer  to  pass  to  the HSTS read function. If you use the CUR-
       LOPT_HSTSREADFUNCTION(3) option, this is the pointer you get as input in
       the 3rd argument to the callback.

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

DEFAULT
       NULL

PROTOCOLS
       This functionality affects http only

EXAMPLE
       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_HSTSREADFUNCTION callback */
           curl_easy_setopt(curl, CURLOPT_HSTSREADDATA, &this);

           curl_easy_perform(curl);
         }
       }

AVAILABILITY
       Added in curl 7.74.0

RETURN VALUE
       This returns CURLE_OK.

SEE ALSO
       CURLOPT_HSTS(3),  CURLOPT_HSTSREADFUNCTION(3), CURLOPT_HSTSWRITEDATA(3),
       CURLOPT_HSTSWRITEFUNCTION(3)

libcurl                            2026-07-12           CURLOPT_HSTSREADDATA(3)

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