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+System-private functions are functions private to the system, which no normal user is entitled to access; these functions normally have an [[access control]] value of NIL.
+
+# (sys-access-control arg)
+
+System private. Takes one argument. Returns the access control list of its argument.
+
+# (sys-readable arg user)
+
+System private. Takes two arguments. Returns TRUE if the first argument is readable by the reader represented by the second argument; else NIL.
+