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function is not described

wp_parse_auth_cookie() WP 2.7.0

Parse a cookie into its components

This is a pluggable function, and it can be replaced from plugin. It means that this function is defined (works) only after all plugins are connected (included), but before this moment the function has not yet been defined... Therefore, you cannot call this and all functions depended on this function directly from a plugin code. It must be called via hook plugins_loaded or later, for example on hook init.

Function replacement (override) — in a plugin you can create a function with the same name, then it will replace this function.

No Hooks.

Return

Array/false. Authentication cookie components

Usage

wp_parse_auth_cookie( $cookie, $scheme );
$cookie(string)

Default: ''
$scheme(string)
The cookie scheme to use: auth, secure_auth, or logged_in
Default: ''

Code of wp parse auth cookie: wp-includes/pluggable.php VER 5.0.3

<?php
function wp_parse_auth_cookie($cookie = '', $scheme = '') {
	if ( empty($cookie) ) {
		switch ($scheme){
			case 'auth':
				$cookie_name = AUTH_COOKIE;
				break;
			case 'secure_auth':
				$cookie_name = SECURE_AUTH_COOKIE;
				break;
			case "logged_in":
				$cookie_name = LOGGED_IN_COOKIE;
				break;
			default:
				if ( is_ssl() ) {
					$cookie_name = SECURE_AUTH_COOKIE;
					$scheme = 'secure_auth';
				} else {
					$cookie_name = AUTH_COOKIE;
					$scheme = 'auth';
				}
	    }

		if ( empty($_COOKIE[$cookie_name]) )
			return false;
		$cookie = $_COOKIE[$cookie_name];
	}

	$cookie_elements = explode('|', $cookie);
	if ( count( $cookie_elements ) !== 4 ) {
		return false;
	}

	list( $username, $expiration, $token, $hmac ) = $cookie_elements;

	return compact( 'username', 'expiration', 'token', 'hmac', 'scheme' );
}