diff --git a/IPhreeqc_interface.F90 b/IPhreeqc_interface.F90
index 7f66f11d..e80b2c50 100644
--- a/IPhreeqc_interface.F90
+++ b/IPhreeqc_interface.F90
@@ -1,4 +1,4 @@
-#ifdef IPHREEQC_MODULE
+#ifndef IPHREEQC_NO_FORTRAN_MODULE
 MODULE IPhreeqc
 implicit none
 SAVE
@@ -685,7 +685,7 @@ INTEGER FUNCTION LoadDatabase(id, filename)
         END FUNCTION LoadDatabaseF
     END INTERFACE
     INTEGER, INTENT(in) :: id
-    CHARACTER(len=*), INTENT(inout) :: filename
+    CHARACTER(len=*), INTENT(in) :: filename
 	LoadDatabase = LoadDatabaseF(id, trim(filename)//C_NULL_CHAR)
 	return
 END FUNCTION LoadDatabase
@@ -702,7 +702,7 @@ INTEGER FUNCTION LoadDatabaseString(id, input)
         END FUNCTION LoadDatabaseStringF
     END INTERFACE
     INTEGER, INTENT(in) :: id
-    CHARACTER(len=*), INTENT(inout) :: input
+    CHARACTER(len=*), INTENT(in) :: input
 	LoadDatabaseString = LoadDatabaseStringF(id, trim(input)//C_NULL_CHAR)
 	return
 END FUNCTION LoadDatabaseString
@@ -779,7 +779,7 @@ INTEGER FUNCTION RunFile(id, filename)
         END FUNCTION RunFileF
     END INTERFACE
     INTEGER, INTENT(in) :: id
-    CHARACTER(len=*), INTENT(inout) :: filename
+    CHARACTER(len=*), INTENT(in) :: filename
 	RunFile = RunFileF(id, trim(filename)//C_NULL_CHAR)
 	return
 END FUNCTION RunFile
@@ -796,7 +796,7 @@ INTEGER FUNCTION RunString(id, input)
         END FUNCTION RunStringF
     END INTERFACE
     INTEGER, INTENT(in) :: id
-    CHARACTER(len=*), INTENT(inout) :: input
+    CHARACTER(len=*), INTENT(in) :: input
 	RunString = RunStringF(id, trim(input)//C_NULL_CHAR)
 	return
 END FUNCTION RunString
@@ -810,22 +810,22 @@ INTEGER FUNCTION SetBasicFortranCallback(id, fcn)
 			IMPLICIT NONE
             INTEGER(KIND=C_INT), INTENT(in) :: id
             INTERFACE
-                INTEGER(KIND=C_INT) FUNCTION fcn(x1, x2, str, l) BIND(C)
+                REAL(KIND=C_DOUBLE) FUNCTION fcn(x1, x2, str, l) BIND(C)
                     USE ISO_C_BINDING
-                    INTEGER(KIND=C_INT), INTENT(inout) :: l
-                    REAL(KIND=C_DOUBLE), INTENT(inout) :: x1, x2
-                    CHARACTER(KIND=C_CHAR), INTENT(out) :: str(*)
+                    INTEGER(KIND=C_INT), INTENT(in) :: l
+                    REAL(KIND=C_DOUBLE), INTENT(in) :: x1, x2
+                    CHARACTER(KIND=C_CHAR), INTENT(in) :: str(*)
                 END FUNCTION fcn
            END INTERFACE
         END FUNCTION SetBasicFortranCallbackF
     END INTERFACE
     INTEGER, INTENT(in) :: id     
     INTERFACE
-        INTEGER(KIND=C_INT) FUNCTION fcn(x1, x2, str, l) BIND(C)
+        REAL(KIND=C_DOUBLE) FUNCTION fcn(x1, x2, str, l) BIND(C)
             USE ISO_C_BINDING
-            INTEGER(KIND=C_INT), INTENT(inout) :: l
-            REAL(KIND=C_DOUBLE), INTENT(inout) :: x1, x2
-            CHARACTER(KIND=C_CHAR), INTENT(out) :: str(*)
+            INTEGER(KIND=C_INT), INTENT(in) :: l
+            REAL(KIND=C_DOUBLE), INTENT(in) :: x1, x2
+            CHARACTER(KIND=C_CHAR), INTENT(in) :: str(*)
         END FUNCTION fcn
     END INTERFACE
 	SetBasicFortranCallback = SetBasicFortranCallbackF(id, fcn)
diff --git a/IPhreeqc_interface_F.cpp b/IPhreeqc_interface_F.cpp
index 47f78bd2..2bca195a 100644
--- a/IPhreeqc_interface_F.cpp
+++ b/IPhreeqc_interface_F.cpp
@@ -1,4 +1,4 @@
-#ifdef IPHREEQC_MODULE
+#ifndef IPHREEQC_NO_FORTRAN_MODULE
 #include <ctype.h>   /* isgraph */
 #include <stdlib.h>  /* malloc */
 #include <memory.h>  /* memcpy */
diff --git a/fwrap.cpp b/fwrap.cpp
index e7266c1c..ae23e5dd 100644
--- a/fwrap.cpp
+++ b/fwrap.cpp
@@ -1,5 +1,5 @@
 
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include <ctype.h>   /* isgraph */
 #include <stdlib.h>  /* malloc */
 #include <memory.h>  /* memcpy */
diff --git a/fwrap.h b/fwrap.h
index 66332c92..0f2740f5 100644
--- a/fwrap.h
+++ b/fwrap.h
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #ifndef __FWRAP__H
 #define __FWRAP__H
 
diff --git a/fwrap1.cpp b/fwrap1.cpp
index cb533a86..e7a1c377 100644
--- a/fwrap1.cpp
+++ b/fwrap1.cpp
@@ -1,3 +1,4 @@
+#ifdef NO_IPHREEQC_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
@@ -19,4 +20,5 @@ extern "C" {
 }
 #endif
 
+#endif
 #endif
\ No newline at end of file
diff --git a/fwrap2.cpp b/fwrap2.cpp
index eaca047c..43565226 100644
--- a/fwrap2.cpp
+++ b/fwrap2.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
diff --git a/fwrap3.cpp b/fwrap3.cpp
index 198e0bc9..aff17195 100644
--- a/fwrap3.cpp
+++ b/fwrap3.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
diff --git a/fwrap4.cpp b/fwrap4.cpp
index a4aff5b7..74a12028 100644
--- a/fwrap4.cpp
+++ b/fwrap4.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
diff --git a/fwrap5.cpp b/fwrap5.cpp
index 88f4ac55..f585a047 100644
--- a/fwrap5.cpp
+++ b/fwrap5.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
diff --git a/fwrap6.cpp b/fwrap6.cpp
index ab95e8a3..0887c900 100644
--- a/fwrap6.cpp
+++ b/fwrap6.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
diff --git a/fwrap7.cpp b/fwrap7.cpp
index d961654a..409e7dc4 100644
--- a/fwrap7.cpp
+++ b/fwrap7.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"
 
diff --git a/fwrap8.cpp b/fwrap8.cpp
index 705ab22e..df542a34 100644
--- a/fwrap8.cpp
+++ b/fwrap8.cpp
@@ -1,4 +1,4 @@
-#ifndef IPHREEQC_MODULE
+#ifdef IPHREEQC_NO_FORTRAN_MODULE
 #include "IPhreeqc.h"
 #include "fwrap.h"