diff --git a/build_linux64/libamscppperm1.linux64.a b/build_linux64/libamscppperm1.linux64.a
index ac64061..1c16a9d 100644
Binary files a/build_linux64/libamscppperm1.linux64.a and b/build_linux64/libamscppperm1.linux64.a differ
diff --git a/build_linux64/objstore/permutation_basic.o b/build_linux64/objstore/permutation_basic.o
index 3fa13c3..5828a9e 100644
Binary files a/build_linux64/objstore/permutation_basic.o and b/build_linux64/objstore/permutation_basic.o differ
diff --git a/build_linux64/tests b/build_linux64/tests
index d0c2f0e..8f902fd 100644
Binary files a/build_linux64/tests and b/build_linux64/tests differ
diff --git a/include/amscppperm1/amscppperm1.hpp b/include/amscppperm1/amscppperm1.hpp
index e40581b..eff8a01 100644
--- a/include/amscppperm1/amscppperm1.hpp
+++ b/include/amscppperm1/amscppperm1.hpp
@@ -14,13 +14,16 @@ namespace perm
 //Basic operations on preallocated buffers
 //for later C library export
 
+static const int perm_success = 0;
+static const int perm_failure = -1;
+
 int factorial(int n);
 
 int index_to_mindex(int index, int *mindex, int ndim);
 
 int mindex_to_index(int *mindex, int ndim);
-void mindex_to_perm(int *mindex, int *perm, int ndim);
-void perm_to_mindex(int *perm, int *mindex, int ndim);
+int mindex_to_perm(int *mindex, int *perm, int *wrk, int ndim);
+int perm_to_mindex(int *perm, int *mindex, int *wrk, int ndim);
 
 bool perm_valid(int *perm, int ndim);
 
diff --git a/src/amscppperm1/permutation_basic.cpp b/src/amscppperm1/permutation_basic.cpp
index 74833cc..e18aa3a 100644
--- a/src/amscppperm1/permutation_basic.cpp
+++ b/src/amscppperm1/permutation_basic.cpp
@@ -101,6 +101,20 @@ namespace perm
         return ret;
     }
 
+    int mindex_to_perm(int *mindex, int *perm, int *wrk, int ndim)
+    {
+        int ret = -1;
+
+        return ret;
+    }
+    
+    int perm_to_mindex(int *perm, int *mindex, int *wrk, int ndim)
+    {
+        int ret = -1;
+        
+        return ret;
+    }
+
 
 }; //end namespace perm
 }; //end namespace ams
\ No newline at end of file