CURLOPT_COOKIELIST(3)

NAME
CURLOPT_COOKIELIST - add to or manipulate cookies held in memory

SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_COOKIELIST,
                          char *cookie);

DESCRIPTION
Pass a char pointer to a cookie string. Such a cookie can be either a single line in Netscape / Mozilla format or just regular HTTP-style header (Set-Cookie: ...) format. This option also enables the cookie engine. This adds that single cookie to the internal cookie store. We strongly advice against loading cookies from an HTTP header file, as that is an inferior data exchange format. Exercise caution if you are using this option and multiple transfers may occur. If you use the Set-Cookie format and the string does not specify a domain, then the cookie is sent for any domain (even after redirects are followed) and cannot be modified by a server-set cookie. If a server sets a cookie of the same name (or maybe you have imported one) then both are sent on future transfers to that server, likely not what you intended. To address these issues set a domain in Set-Cookie (doing that includes subdomains) or much better: use the Netscape file format. Additionally, there are commands available that perform actions if you pass in these exact strings:

ALL erases all cookies held in memory

SESS
    erases all session cookies held in memory

FLUSH
    writes all known cookies to the file specified by CURLOPT_COOKIEJAR(3)

RELOAD
    loads all cookies from the files specified by CURLOPT_COOKIEFILE(3)

DEFAULT
NULL

PROTOCOLS
HTTP

EXAMPLE
/* an inline import of a cookie in Netscape format. */
#define SEP  "\t"  /* Tab separates the fields */
int main(void)
{
  char *my_cookie =
    "example.com"    /* Hostname */
    SEP "FALSE"      /* Include subdomains */
    SEP "/"          /* Path */
    SEP "FALSE"      /* Secure */
    SEP "0"          /* Expiry in epoch time format. 0 == Session */
    SEP "foo"        /* Name */
    SEP "bar";       /* Value */
  CURL *curl = curl_easy_init();
  if(curl) {
    /* my_cookie is imported immediately via CURLOPT_COOKIELIST. */
    curl_easy_setopt(curl, CURLOPT_COOKIELIST, my_cookie);
    /* The list of cookies in cookies.txt are not be imported until right
       before a transfer is performed. Cookies in the list that have the same
       hostname, path and name as in my_cookie are skipped. That is because
       libcurl has already imported my_cookie and it's considered a "live"
       cookie. A live cookie is not replaced by one read from a file.
    */
    curl_easy_setopt(curl, CURLOPT_COOKIEFILE, "cookies.txt");  /* import */
    /* Cookies are exported after curl_easy_cleanup is called. The server
       may have added, deleted or modified cookies by then. The cookies that
       were skipped on import are not exported.
    */
    curl_easy_setopt(curl, CURLOPT_COOKIEJAR, "cookies.txt");  /* export */
    curl_easy_perform(curl);  /* cookies imported from cookies.txt */
    curl_easy_cleanup(curl);  /* cookies exported to cookies.txt */
  }
}

Cookie file format
The cookie file format and general cookie concepts in curl are described online here: https://curl.se/docs/http-cookies.html

AVAILABILITY
ALL was added in 7.14.1 SESS was added in 7.15.4 FLUSH was added in 7.17.1 RELOAD was added in 7.39.0

RETURN VALUE
Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or CURLE_OUT_OF_MEMORY if there was insufficient heap space.

SEE ALSO
CURLINFO_COOKIELIST(3), CURLOPT_COOKIE(3), CURLOPT_COOKIEFILE(3), CURLOPT_COOKIEJAR(3)