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function is not described

wp_get_mu_plugins() WP 3.0.0

Retrieve an array of must-use plugin files.

The default directory is wp-content/mu-plugins. To change the default directory manually, define WPMU_PLUGIN_DIR and WPMU_PLUGIN_URL in wp-config.php.

No Hooks.

Return

Array. Files to include.

Usage

wp_get_mu_plugins();

Code of wp get mu plugins: wp-includes/load.php VER 5.0.3

<?php
function wp_get_mu_plugins() {
	$mu_plugins = array();
	if ( !is_dir( WPMU_PLUGIN_DIR ) )
		return $mu_plugins;
	if ( ! $dh = opendir( WPMU_PLUGIN_DIR ) )
		return $mu_plugins;
	while ( ( $plugin = readdir( $dh ) ) !== false ) {
		if ( substr( $plugin, -4 ) == '.php' )
			$mu_plugins[] = WPMU_PLUGIN_DIR . '/' . $plugin;
	}
	closedir( $dh );
	sort( $mu_plugins );

	return $mu_plugins;
}