CURLOPT_HSTSREADFUNCTION(3)curl_easy_setopt optionsCURLOPT_HSTSREADFUNCTION(3)
NAME
CURLOPT_HSTSREADFUNCTION - read callback for HSTS hosts
SYNOPSIS
#include <curl/curl.h>
CURLSTScode hstsread(CURL *easy, struct curl_hstsentry *sts, void *userp);
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HSTSREADFUNCTION, hstsread);
DESCRIPTION
Pass a pointer to your callback function, as the prototype shows above.
This callback function gets called by libcurl repeatedly when it popu-
lates the in-memory HSTS cache.
Set the userp argument with the CURLOPT_HSTSREADDATA(3) option or it
will be NULL.
When this callback is invoked, the sts pointer points to a populated
struct: Copy the host name to 'name' (no longer than 'namelen' bytes).
Make it null-terminated. Set 'includeSubDomains' to TRUE or FALSE. Set
'expire' to a date stamp or a zero length string for *forever* (wrong
date stamp format might cause the name to not get accepted)
The callback should return CURLSTS_OK if it returns a name and is pre-
pared to be called again (for another host) or CURLSTS_DONE if it has
no entry to return. It can also return CURLSTS_FAIL to signal error.
Returning CURLSTS_FAIL will stop the transfer from being performed and
make CURLE_ABORTED_BY_CALLBACK get returned.
This option does not enable HSTS, you need to use CURLOPT_HSTS_CTRL(3)
to do that.
DEFAULT
NULL - no callback.
PROTOCOLS
This feature is only used for HTTP(S) transfer.
EXAMPLE
{
/* set HSTS read callback */
curl_easy_setopt(curl, CURLOPT_HSTSREADFUNCTION, hstsread);
/* pass in suitable argument to the callback */
curl_easy_setopt(curl, CURLOPT_HSTSREADDATA, &hstspreload[0]);
result = curl_easy_perform(curl);
}
AVAILABILITY
Added in 7.74.0
RETURN VALUE
This will return CURLE_OK.
SEE ALSO
CURLOPT_HSTSREADDATA(3), CURLOPT_HSTSWRITEFUNCTION(3), CURLOPT_HSTS(3),
CURLOPT_HSTS_CTRL(3),
libcurl 7.81.0 November 26, 2021 CURLOPT_HSTSREADFUNCTION(3)
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