Si el usuario inició sesión en WordPress
if ( is_user_logged_in() ) {
// your code for logged in user
} else {
// your code for logged out user
}
Glorious Gnat
if ( is_user_logged_in() ) {
// your code for logged in user
} else {
// your code for logged out user
}<?php
add_action('admin_init', 'wpse74389_check_username');
function wpse74389_check_username()
{
$user = wp_get_current_user();
if($user && isset($user->user_login) && 'username_to_check' == $user->user_login) {
// do stuff
}
}