1CURLOPT_HSTS_CTRL(3) curl_easy_setopt options CURLOPT_HSTS_CTRL(3)
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6 CURLOPT_HSTS_CTRL - control HSTS behavior
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9 #include <curl/curl.h>
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11 #define CURLHSTS_ENABLE (1<<0)
12 #define CURLHSTS_READONLYFILE (1<<1)
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14 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HSTS_CTRL, long bitmask);
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17 HSTS (HTTP Strict Transport Security) means that an HTTPS server can
18 instruct the client to not contact it again over clear-text HTTP for a
19 certain period into the future. libcurl will then automatically redi‐
20 rect HTTP attempts to such hosts to instead use HTTPS. This is done by
21 libcurl retaining this knowledge in an in-memory cache.
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23 Populate the long bitmask with the correct set of features to instruct
24 libcurl how to handle HSTS for the transfers using this handle.
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27 CURLHSTS_ENABLE
28 Enable the in-memory HSTS cache for this handle.
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30 CURLHSTS_READONLYFILE
31 Make the HSTS file (if specified) read-only - makes libcurl not
32 save the cache to the file when closing the handle.
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35 0. HSTS is disabled by default.
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38 HTTPS and HTTP
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41 CURL *curl = curl_easy_init();
42 if(curl) {
43 curl_easy_setopt(curl, CURLOPT_HSTS_CTRL, CURLHSTS_ENABLE);
44 curl_easy_perform(curl);
45 }
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48 Added in 7.74.0
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51 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
52 if not.
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55 CURLOPT_HSTS(3), CURLOPT_CONNECT_TO(3), CURLOPT_RESOLVE(3), CUR‐
56 LOPT_ALTSVC(3),
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60libcurl 7.85.0 May 17, 2022 CURLOPT_HSTS_CTRL(3)