CURLINFO_APPCONNECT_TIME man page
CURLINFO_APPCONNECT_TIME — get the time until the SSL/SSH handshake is completed
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_APPCONNECT_TIME, double *timep);
Pass a pointer to a double to receive the time, in seconds, it took from the start until the SSL/SSH connect/handshake to the remote host was completed. This time is most often very near to the CURLINFO_PRETRANSFER_TIME(3) time, except for cases such as HTTP pipelining where the pretransfer time can be delayed due to waits in line for the pipeline and more.
See also the TIMES overview in the curl_easy_getinfo(3) man page.
Added in 7.19.0
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.