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function is not described

is_network_only_plugin() WP 3.0.0

Checks for "Network: true" in the plugin header to see if this should be activated only as a network wide plugin. The plugin would also work when Multisite is not enabled.

Checks for "Site Wide Only: true" for backward compatibility.

No Hooks.

Return

true/false. True if plugin is network only, false otherwise.

Usage

is_network_only_plugin( $plugin );
$plugin(string) (required)
Path to the main plugin file from plugins directory.

Code of is network only plugin: wp-admin/includes/plugin.php VER 5.0.3

<?php
function is_network_only_plugin( $plugin ) {
	$plugin_data = get_plugin_data( WP_PLUGIN_DIR . '/' . $plugin );
	if ( $plugin_data )
		return $plugin_data['Network'];
	return false;
}