diff --git a/Editor/Installer/BashUtil.cs b/Editor/Installer/BashUtil.cs
index 9927ab0..0a6bc21 100644
--- a/Editor/Installer/BashUtil.cs
+++ b/Editor/Installer/BashUtil.cs
@@ -52,7 +52,12 @@ namespace HybridCLR.Editor.Installer
 
         public static bool ExistProgram(string prog)
         {
+#if UNITY_EDITOR_WIN
             return RunCommand(".", "where", new string[] {prog}) == 0;
+#elif UNITY_EDITOR_OSX || UNITY_EDITOR_LINUX
+            return RunCommand(".", "which", new string[] {prog}) == 0;
+#endif
+            return false;
         }