From 1a024d2df5fc2bc5226b2797ee62974cdadaa398 Mon Sep 17 00:00:00 2001
From: Kenneth Skovhede <kenneth@hexad.dk>
Date: Sun, 6 Dec 2015 22:02:48 +0100
Subject: [PATCH] Fixed creating spurious folders on non-windows platforms.
 This fixes #1508.

---
 Duplicati/Library/AutoUpdater/UpdaterManager.cs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Duplicati/Library/AutoUpdater/UpdaterManager.cs b/Duplicati/Library/AutoUpdater/UpdaterManager.cs
index 6a3345551..e9d6587b6 100644
--- a/Duplicati/Library/AutoUpdater/UpdaterManager.cs
+++ b/Duplicati/Library/AutoUpdater/UpdaterManager.cs
@@ -81,13 +81,17 @@ namespace Duplicati.Library.AutoUpdater
             string installdir = null;
             var attempts = new string[] {
                 System.IO.Path.Combine(InstalledBaseDir, "updates"),
-                System.IO.Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles), APPNAME, "updates"),
+
+                // Not defined on Non-Windows
+                string.IsNullOrWhiteSpace(System.Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles)) 
+                    ? null : System.IO.Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.ProgramFiles), APPNAME, "updates"),
+
                 System.IO.Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), APPNAME, "updates"),
                 System.IO.Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), APPNAME, "updates"),
             };
 
             foreach(var p in attempts)
-                if (TestDirectoryIsWriteable(p))
+                if (!string.IsNullOrWhiteSpace(p) && TestDirectoryIsWriteable(p))
                 {
                     installdir = p;
                     break;