From 79b1c42db07e7327ee6ef08d976464afb18a8f44 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 14 Jul 2011 12:47:14 -0600
Subject: [PATCH] Fix #810655 (unable to add new books to calibre on win7)

---
 src/calibre/ptempfile.py | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/calibre/ptempfile.py b/src/calibre/ptempfile.py
index af34408a05..00e415ec74 100644
--- a/src/calibre/ptempfile.py
+++ b/src/calibre/ptempfile.py
@@ -114,7 +114,17 @@ def PersistentTemporaryDirectory(suffix='', prefix='', dir=None):
     '''
     if dir is None:
         dir = base_dir()
-    tdir = tempfile.mkdtemp(suffix, __appname__+"_"+ __version__+"_" +prefix, dir)
+    try:
+        tdir = tempfile.mkdtemp(suffix, __appname__+"_"+ __version__+"_" +prefix, dir)
+    except ValueError:
+        global _base_dir
+        from calibre.constants import filesystem_encoding
+        base_dir()
+        if not isinstance(_base_dir, unicode):
+            _base_dir = _base_dir.decode(filesystem_encoding)
+        dir = dir.decode(filesystem_encoding)
+        tdir = tempfile.mkdtemp(suffix, __appname__+"_"+ __version__+"_" +prefix, dir)
+
     atexit.register(remove_dir, tdir)
     return tdir