diff --git a/sim/run.py b/sim/run.py
index 8f26fe483bec67ea9c110ad504632f1cc8ae451f..3de9e534b28a25158b131a2fd964431c3a0a4731 100755
--- a/sim/run.py
+++ b/sim/run.py
@@ -115,6 +115,7 @@ os.listdir = _mkmock(os.listdir)
 os.stat = _mkmock(os.stat)
 os.statvfs = _mkmock(os.statvfs)
 os.mkdir = _mkmock(os.mkdir)
+os.unlink = _mkmock(os.unlink)
 builtins.open = _mkmock(builtins.open)
 
 orig_stat = os.stat