diff --git a/bin/bak b/bin/bak
index 4efb3ff..4b60d1a 100755
--- a/bin/bak
+++ b/bin/bak
@@ -10,5 +10,8 @@ bakrotate() {
   fi
 }
 
-bakrotate "$1.bak"
-cp $1 $1.bak
+for file in $@
+do
+  bakrotate "$file.bak"
+  cp $file $file.bak
+done