diff --git a/src/MrRio/ShellWrap.php b/src/MrRio/ShellWrap.php
index 8ba4fff..32ab329 100644
--- a/src/MrRio/ShellWrap.php
+++ b/src/MrRio/ShellWrap.php
@@ -134,7 +134,13 @@ private static function __run($arguments)
             2 => array('pipe', 'w') // Stderr
         );
 
-        $process = proc_open($shell, $descriptor_spec, $pipes);
+        // If you use function chdir() to change working directory to a different directory first, following two
+        // statements should still return same directories. However, in Travis CI they return different directories back
+        // (the 2nd one returns the directory where the PHP script was invoked).
+        //     1. getcwd()
+        //     2. (string) ShellWrap::pwd()
+        // Thus we have the 4th parameter (getcwd()) specified explicitly here, also ideally it's unnecessary.
+        $process = proc_open($shell, $descriptor_spec, $pipes, getcwd());
 
         if (is_resource($process)) {