diff --git a/python_appimage/appimage/relocate.py b/python_appimage/appimage/relocate.py
index 8bf9920..4d2db16 100644
--- a/python_appimage/appimage/relocate.py
+++ b/python_appimage/appimage/relocate.py
@@ -34,6 +34,15 @@ def _get_tk_version(python_pkg):
             raise RuntimeError('could not guess Tcl/Tk version')
 
 
+def _get_tk_libdir(version):
+    try:
+        library = system(('tclsh' + version,), stdin='puts [info library]')
+    except SystemError:
+        raise RuntimeError('could not locate Tcl/Tk' + version + ' library')
+
+    return os.path.dirname(library)
+
+
 def tcltk_env_string(python_pkg):
     '''Environment for using AppImage's TCl/Tk
     '''
@@ -280,22 +289,13 @@ def relocate_python(python=None, appdir=None):
         tcltkdir = APPDIR_SHARE + '/tcltk'
         if (not os.path.exists(tcltkdir + '/tcl' + tk_version)) or             \
            (not os.path.exists(tcltkdir + '/tk' + tk_version)):
-            hostdir = '/usr/share/tcltk'
-            if os.path.exists(hostdir):
-                make_tree(APPDIR_SHARE)
-                copy_tree(hostdir, tcltkdir)
-            else:
-                make_tree(tcltkdir)
-                tclpath = '/usr/share/tcl' + tk_version
-                if not tclpath:
-                    raise ValueError('could not find ' + tclpath)
-                copy_tree(tclpath, tcltkdir + '/tcl' + tk_version)
-
-                tkpath = '/usr/share/tk' + tk_version
-                if not tkpath:
-                    raise ValueError('could not find ' + tkpath)
-                copy_tree(tkpath, tcltkdir + '/tk' + tk_version)
-
+            libdir = _get_tk_libdir(tk_version)
+            log('INSTALL', 'Tcl/Tk' + tk_version)
+            make_tree(tcltkdir)
+            tclpath = libdir + '/tcl' + tk_version
+            copy_tree(tclpath, tcltkdir + '/tcl' + tk_version)
+            tkpath = libdir + '/tk' + tk_version
+            copy_tree(tkpath, tcltkdir + '/tk' + tk_version)
 
     # Copy any SSL certificate
     cert_file = os.getenv('SSL_CERT_FILE')
diff --git a/python_appimage/utils/compat.py b/python_appimage/utils/compat.py
index 17e0e37..8776bc0 100644
--- a/python_appimage/utils/compat.py
+++ b/python_appimage/utils/compat.py
@@ -1,7 +1,7 @@
 import sys
 
 
-__all__ = ['decode', 'find_spec']
+__all__ = ['decode', 'encode', 'find_spec']
 
 
 def decode(s):
@@ -13,6 +13,15 @@ def decode(s):
         return str(s)
 
 
+def encode(s):
+    '''Encode Python 3 str as bytes
+    '''
+    try:
+        return s.encode()
+    except Exception:
+        return str(s)
+
+
 if sys.version_info[0] == 2:
     from collections import namedtuple
     import imp
diff --git a/python_appimage/utils/system.py b/python_appimage/utils/system.py
index 1b9ba19..03fde7d 100644
--- a/python_appimage/utils/system.py
+++ b/python_appimage/utils/system.py
@@ -2,7 +2,7 @@ import os
 import re
 import subprocess
 
-from .compat import decode
+from .compat import decode, encode
 from .log import debug, log
 
 
@@ -15,7 +15,7 @@ except NameError:
     basestring = (str, bytes)
 
 
-def system(args, exclude=None):
+def system(args, exclude=None, stdin=None):
     '''System call with capturing output
     '''
     cmd = ' '.join(args)
@@ -29,9 +29,15 @@ def system(args, exclude=None):
         exclude = list(exclude)
     exclude.append('fuse: warning:')
 
+    if stdin:
+        in_arg = subprocess.PIPE
+        stdin = encode(stdin)
+    else:
+        in_arg = None
+
     p = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE,
-                         stderr=subprocess.PIPE)
-    out, err = p.communicate()
+                         stderr=subprocess.PIPE, stdin=in_arg)
+    out, err = p.communicate(input=stdin)
     if err:
         err = decode(err)
         stripped = [line for line in err.split(os.linesep) if line]