Remove RISCOS support
diff --git a/Lib/test/test_mailbox.py b/Lib/test/test_mailbox.py
index 59def94..64ed07c 100644
--- a/Lib/test/test_mailbox.py
+++ b/Lib/test/test_mailbox.py
@@ -1687,7 +1687,7 @@
t = int(time.time() % 1000000)
pid = self._counter
self._counter += 1
- filename = os.extsep.join((str(t), str(pid), "myhostname", "mydomain"))
+ filename = ".".join((str(t), str(pid), "myhostname", "mydomain"))
tmpname = os.path.join(self._dir, "tmp", filename)
newname = os.path.join(self._dir, dir, filename)
fp = open(tmpname, "w")