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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 by a plugin. It means that this function is defined (works) only after all plugins are loaded (included), but before this moment this function has not defined. Therefore, you cannot call this and all functions depended on this function directly from a plugin code. It must be called on plugins_loaded hook or later, for example on init hook.

Function replacement (override) — in a plugin you can create a function with the same name, then it 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 5.1.1

<?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' );
}