--- a/mercurial/bundlerepo.py
+++ b/mercurial/bundlerepo.py
@@ -206,3 +206,6 @@ class bundlerepository(localrepo.localre
         else:
             return filelog.filelog(self.opener, f)
 
+    def close(self):
+        """Close assigned bundle file immediately."""
+        self.bundlefile.close()

--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -1811,7 +1811,7 @@ def incoming(ui, repo, source="default",
             ui.write("\n")
 
     if cleanup:
-        os.close(fd)
+        other.close()                   # explicit close for unlink
         os.unlink(cleanup)
 
 def init(ui, dest="."):