From ff955182202a3f0507e4d6363467d6d895b068a3 Mon Sep 17 00:00:00 2001
From: Rodrigue Cloutier <rodcloutier@gmail.com>
Date: Mon, 4 Jul 2016 12:52:21 -0400
Subject: [PATCH] Only copy tcltk related files if exists and not present.
 Fixes #929

---
 virtualenv.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/virtualenv.py b/virtualenv.py
index 61ccfb2ad..36cd7824a 100755
--- a/virtualenv.py
+++ b/virtualenv.py
@@ -1074,7 +1074,8 @@ def copy_tcltk(src, dest, symlink):
     for name in ['tcl', 'tk']:
         srcdir = src + '/tcl/' + name + libver
         dstdir = dest + '/tcl/' + name + libver
-        copyfileordir(srcdir, dstdir, symlink)
+        if os.path.exists(srcdir) and not os.path.exists(dstdir):
+            copyfileordir(srcdir, dstdir, symlink)
 
 def subst_path(prefix_path, prefix, home_dir):
     prefix_path = os.path.normpath(prefix_path)