CURLOPT_COOKIEFILE (3) - Linux Man Pages
CURLOPT_COOKIEFILE: file name to read cookies from
NAMECURLOPT_COOKIEFILE - file name to read cookies from
DESCRIPTIONPass a pointer to a zero terminated string as parameter. It should point to the file name of your file holding cookie data to read. The cookie data can be in either the old Netscape / Mozilla cookie data format or just regular HTTP-style headers dumped to a file.
It also enables the cookie engine, making libcurl parse and send cookies on subsequent requests with this handle.
Given an empty or non-existing file or by passing the empty string ("") to this option, you can enable the cookie engine without reading any initial cookies.
This option only reads cookies. To make libcurl write cookies to file, see CURLOPT_COOKIEJAR(3).