diff --git a/lib/shell.js b/lib/shell.js
index db98ced..2c29e71 100644
--- a/lib/shell.js
+++ b/lib/shell.js
@@ -75,7 +75,7 @@ var ShellObject = function() {
 
     this.exec = function(cmd, stdOutPath, stdErrPath) {
         var stdout, stderr;
-		var seed = parseInt(Math.random() * 10000);
+        var seed = parseInt(Math.random() * 10000);
         var stdOutPath = (typeof(stdOutPath) === "undefined" ? "tmp\\stdout_" + seed + ".txt" : stdOutPath);
         var stdErrPath = (typeof(stdErrPath) === "undefined" ? "tmp\\stderr_" + seed + ".txt" : stdErrPath);