Issue 16584: in filecomp._cmp, catch IOError as well as os.error.
Patch by Till Maas.
diff --git a/Misc/ACKS b/Misc/ACKS
index 660f52c..9e09abd 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -626,6 +626,7 @@
 Jim Lynch
 Mikael Lyngvig
 Martin von Löwis
+Till Maas
 Jeff MacDonald
 John Machin
 Andrew I MacIntyre