**************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
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*
* Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
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* furnished to do so, under the terms of the COPYING file.
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* KIND, either express or implied.
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**************************************************************************

CURLOPT_FILETIME - get the modification time of the remote resource #include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FILETIME, long gettime); Pass a long. If it is 1, libcurl will attempt to get the modification time of the remote document in this operation. This requires that the remote server sends the time or replies to a time querying command. The curl_easy_getinfo(3) function with the CURLINFO_FILETIME(3) argument can be used after a transfer to extract the received time (if any). 0 HTTP, FTP, SFTP, FILE

curl = curl_easy_init();
if(curl) {
 curl_easy_setopt(curl, CURLOPT_URL, url);
 /* Ask for filetime */
 curl_easy_setopt(curl, CURLOPT_FILETIME, 1L);
 res = curl_easy_perform(curl);
 if(CURLE_OK == res) {
 res = curl_easy_getinfo(curl, CURLINFO_FILETIME, &filetime);
 if((CURLE_OK == res) && (filetime >= 0)) {
 time_t file_time = (time_t)filetime;
 printf("filetime %s: %s", filename, ctime(&file_time));
 }
 }
 /* always cleanup */
 curl_easy_cleanup(curl);
}

Always, for SFTP since 7.49.0 Returns CURLE_OK curl_easy_getinfo "(3), "