diff --git a/system/bin/install_plugin.php b/system/bin/install_plugin.php
index 0fb7f5f6..c26578dc 100644
--- a/system/bin/install_plugin.php
+++ b/system/bin/install_plugin.php
@@ -1,22 +1,22 @@
 <?php
 
-if(php_sapi_name() != "cli") {
+if(PHP_SAPI !== 'cli') {
 	die('This script can be run only in command line mode.');
 }
 
-require_once '../../common.php';
+require_once __DIR__ . '/../../common.php';
 require_once SYSTEM . 'functions.php';
 require_once SYSTEM . 'init.php';
 require_once SYSTEM . 'hooks.php';
 require_once LIBS . 'plugins.php';
 
-if($argc != 2) {
+if($argc !== 2) {
 	exit('This command expects one parameter: zip file name (plugin)' . PHP_EOL);
 }
 
 $path_to_file = $argv[1];
 $ext = strtolower(pathinfo($path_to_file, PATHINFO_EXTENSION));
-if($ext != 'zip') {// check if it is zipped/compressed file
+if($ext !== 'zip') {// check if it is zipped/compressed file
 	exit('Please install only .zip files.' . PHP_EOL);
 }
 
@@ -35,5 +35,4 @@ if(Plugins::install($path_to_file)) {
 else
 	echo 'ERROR: ' . Plugins::getError();
 
-echo PHP_EOL;
-?>
\ No newline at end of file
+echo PHP_EOL;
\ No newline at end of file