lispdoc  results for xor 
(bitxor bitarray1 bitarray2 &optional resultbitarray)  Function: Perform a bitwise LOGXOR on the elements of BITARRAY1 and BITARRAY2, putting the results in RESULTBITARRAY. If RESULTBITARRAY is T, BITARRAY1 is used. If RESULTBITARRAY is NIL or omitted, a new array is created. All the arrays must have the same rank and dimensions.

Mentioned in: HyperSpec  Function BITAND, BITANDC1, BITANDC2, BITEQV, BITIOR, BITNAND, BITNOR, BITNOT, BITORC1, BITORC2, BITXOR Successful Lisp  chapter18  
boolexor  Variable: Boole function op, makes BOOLE return logxor of integer1 and integer2.

Mentioned in: CLtL2  12.7. Logical Operations on Numbers HyperSpec  Constant Variable BOOLE1, BOOLE2, BOOLEAND, BOOLEANDC1, BOOLEANDC2, BOOLEC1, BOOLEC2, BOOLECLR, BOOLEEQV, BOOLEIOR, BOOLENAND, BOOLENOR, BOOLEORC1, BOOLEORC2, BOOLESET, BOOLEXOR Successful Lisp  chapter18  
(alexandria.0.dev:xor &rest datums)  Function: Evaluates its arguments one at a time, from left to right. If more then one argument evaluates to a true value no further DATUMS are evaluated, and NIL is returned as both primary and secondary value. If exactly one argument evaluates to true, its value is returned as the primary value after all the arguments have been evaluated, and T is returned as the secondary value. If no arguments evaluate to true NIL is retuned as primary, and T as secondary value.

By Bill Moorier 