CURLOPT_PRIVATE(3) Library Functions Manual CURLOPT_PRIVATE(3) NAME CURLOPT_PRIVATE - store a private pointer SYNOPSIS #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PRIVATE, void *pointer); DESCRIPTION Pass a void * as parameter, pointing to data that should be associated with this curl handle. The pointer can subsequently be retrieved using curl_easy_getinfo(3) with the CURLINFO_PRIVATE(3) option. libcurl itself never does anything with this data. DEFAULT NULL PROTOCOLS All EXAMPLE struct private { void *custom; }; int main(void) { CURL *curl = curl_easy_init(); struct private secrets; if(curl) { struct private *extracted; curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); /* store a pointer to our private struct */ curl_easy_setopt(curl, CURLOPT_PRIVATE, &secrets); curl_easy_perform(curl); /* we can extract the private pointer again too */ curl_easy_getinfo(curl, CURLINFO_PRIVATE, &extracted); } } AVAILABILITY Added in 7.10.3 RETURN VALUE Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. SEE ALSO CURLINFO_PRIVATE(3), CURLOPT_STDERR(3), CURLOPT_VERBOSE(3) libcurl April 26 2024 CURLOPT_PRIVATE(3)