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function is not described

user_admin_url() WP 3.0.0

Retrieves the URL to the admin area for the current user.

Hooks in function
Return

String. Admin URL link with optional path appended.

Usage

user_admin_url( $path, $scheme );
$path(string)
Path relative to the admin URL.
Default: ''
$scheme(string)
The scheme to use. 'http' or 'https' can be passed to force those schemes.
Default: 'admin', which obeys force_ssl_admin() and is_ssl()

Code of user admin url: wp-includes/link-template.php VER 5.0.3

<?php
function user_admin_url( $path = '', $scheme = 'admin' ) {
	$url = network_site_url('wp-admin/user/', $scheme);

	if ( $path && is_string( $path ) )
		$url .= ltrim($path, '/');

	/**
	 * Filters the user admin URL for the current user.
	 *
	 * @since 3.1.0
	 *
	 * @param string $url  The complete URL including scheme and path.
	 * @param string $path Path relative to the URL. Blank string if
	 *                     no path is specified.
	 */
	return apply_filters( 'user_admin_url', $url, $path );
}