Add getfilesystemencoding() for python < 2.3.

diff --git a/src/inout/io.py b/src/inout/io.py
index 68b69130999fdfa2771326449965d07ae8d4734d..f873b67d7b0f9aa4d6b196e23f66dee210d37c62 100644 (file)
--- a/src/inout/io.py
+++ b/src/inout/io.py
@@ -24,15 +24,30 @@ def create_file(file_path):
     f = file(file_name,'w')
     return f
 
+def getfilesystemencoding():
+    try:
+        # sys.getfilesystemencoding() was introduced in Python v2.3
+        return sys.getfilesystemencoding()
+    except AttributeError:
+        return 'ascii'
 
 def os_encode(s):
-    return s.encode(sys.getfilesystemencoding())
+    # Encoding can be None, meaning the default system encoding should
+    # be used.
+    enc = getfilesystemencoding()
+    if enc:
+        return s.encode(enc)
+    else:
+        return s
 
 def os_decode(s):
-    if type(s) == unicode:
+    # Encoding can be None, meaning the default system encoding should
+    # be used.
+    enc = getfilesystemencoding()
+    if type(s) == unicode or not enc:
         return s
     else:
-        return unicode(s,sys.getfilesystemencoding())
+        return unicode(s,enc)
 
 def write(file_path,content):
     f = create_file(file_path)