允许子目录安装。

原型

allow_subdirectory_install()

返回值

(bool)  是否允许子目录安装

源文件

路径:wp-admin/includes/network.php

<?php
...
function allow_subdirectory_install() {
	global $wpdb;
        /**
         * Filters whether to enable the subdirectory installation feature in Multisite.
         *
         * @since 3.0.0
         *
         * @param bool $allow Whether to enable the subdirectory installation feature in Multisite. Default is false.
         */
	if ( apply_filters( 'allow_subdirectory_install', false ) )
		return true;
	if ( defined( 'ALLOW_SUBDIRECTORY_INSTALL' ) && ALLOW_SUBDIRECTORY_INSTALL )
		return true;
	$post = $wpdb->get_row( "SELECT ID FROM $wpdb->posts WHERE post_date < DATE_SUB(NOW(), INTERVAL 1 MONTH) AND post_status = 'publish'" );
	if ( empty( $post ) )
		return true;
	return false;
}
...
?>

其他

英文文档:https://developer.wordpress.org/reference/functions/allow_subdirectory_install/