CURLOPT_HSTS_CTRL(3)       Library Functions Manual       CURLOPT_HSTS_CTRL(3)

NAME
       CURLOPT_HSTS_CTRL - control HSTS behavior

SYNOPSIS
       #include <curl/curl.h>

       #define CURLHSTS_ENABLE       (1<<0)
       #define CURLHSTS_READONLYFILE (1<<1)

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HSTS_CTRL, long bitmask);

DESCRIPTION
       HSTS (HTTP Strict Transport Security) means that an HTTPS server can
       instruct the client to not contact it again over clear-text HTTP for a
       certain period into the future. libcurl then automatically redirects
       HTTP attempts to such hosts to instead use HTTPS. This is done by
       libcurl retaining this knowledge in an in-memory cache.

       Populate the long bitmask with the correct set of features to instruct
       libcurl how to handle HSTS for the transfers using this handle.

BITS
       CURLHSTS_ENABLE
              Enable the in-memory HSTS cache for this handle.

       CURLHSTS_READONLYFILE
              Make the HSTS file (if specified) read-only - makes libcurl not
              save the cache to the file when closing the handle.

DEFAULT
       0. HSTS is disabled by default.

PROTOCOLS
       HTTP

EXAMPLE
       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           curl_easy_setopt(curl, CURLOPT_HSTS_CTRL, (long)CURLHSTS_ENABLE);
           curl_easy_perform(curl);
         }
       }

AVAILABILITY
       Added in 7.74.0

RETURN VALUE
       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
       if not.

SEE ALSO
       CURLOPT_ALTSVC(3), CURLOPT_CONNECT_TO(3), CURLOPT_HSTS(3),
       CURLOPT_RESOLVE(3)

libcurl                          April 26 2024            CURLOPT_HSTS_CTRL(3)