From 41df24137ab0c1a0dfda21714f68257c5a0af730 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 6 Aug 2009 16:26:23 -0600
Subject: [PATCH] On linux, don't use Qt to render covers, etc. if the DISPLAY
 environment variable is unset

---
 src/calibre/gui2/__init__.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/calibre/gui2/__init__.py b/src/calibre/gui2/__init__.py
index 12f6fb2025..9898eb5c13 100644
--- a/src/calibre/gui2/__init__.py
+++ b/src/calibre/gui2/__init__.py
@@ -487,6 +487,8 @@ class Application(QApplication):
 
 def is_ok_to_use_qt():
     global gui_thread
+    if islinux and os.environ.get('DISPLAY', None) is None:
+        return False
     if QApplication.instance() is None:
         QApplication([])
     if gui_thread is None: