diff --git a/src/io/io_private.h b/src/io/io_private.h
index b2e651d60b..0634da69ab 100644
--- a/src/io/io_private.h
+++ b/src/io/io_private.h
@@ -1,5 +1,5 @@
 /*
-Copyright (C) 2001-2008, Parrot Foundation.
+Copyright (C) 2001-2014, Parrot Foundation.
 
 =head1 NAME
 
@@ -165,7 +165,7 @@ struct _ParrotIOData {
 
 /* Get an editable version of the IO_VTABLE structure, typically used during
    vtable initialization. */
-#define IO_EDITABLE_IO_VTABLE(i, idx) ((IO_VTABLE *)(void *)(&((i)->piodata->vtables[(idx)])))
+#define IO_EDITABLE_IO_VTABLE(i, idx) (IO_VTABLE *)(&((i)->piodata->vtables[(idx)]))
 
 
 /* HEADERIZER BEGIN: src/io/utilities.c */
diff --git a/src/io/pipe.c b/src/io/pipe.c
index 3979306f8b..46eac80c1b 100644
--- a/src/io/pipe.c
+++ b/src/io/pipe.c
@@ -1,5 +1,5 @@
 /*
-Copyright (C) 2001-2012, Parrot Foundation.
+Copyright (C) 2001-2014, Parrot Foundation.
 
 =head1 NAME
 
@@ -29,7 +29,6 @@ This file implements the IO_VTABLE for pipes and helper functions.
 static void io_pipe_adv_position(PARROT_INTERP,
     ARGMOD(PMC *handle),
     size_t offset)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -51,7 +50,6 @@ static const STR_VTABLE * io_pipe_get_encoding(PARROT_INTERP,
         __attribute__nonnull__(2);
 
 static INTVAL io_pipe_get_flags(PARROT_INTERP, ARGIN(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static PIOHANDLE io_pipe_get_piohandle(PARROT_INTERP, ARGIN(PMC *handle))
@@ -59,7 +57,6 @@ static PIOHANDLE io_pipe_get_piohandle(PARROT_INTERP, ARGIN(PMC *handle))
         __attribute__nonnull__(2);
 
 static PIOOFF_T io_pipe_get_position(PARROT_INTERP, ARGMOD(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -105,20 +102,17 @@ static PIOOFF_T io_pipe_seek(PARROT_INTERP,
 static void io_pipe_set_eof(PARROT_INTERP,
     ARGMOD(PMC *handle),
     INTVAL is_set)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
 static void io_pipe_set_flags(PARROT_INTERP,
     ARGIN(PMC *handle),
     INTVAL flags)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static void io_pipe_set_position(PARROT_INTERP,
     ARGMOD(PMC *handle),
     PIOOFF_T pos)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -128,7 +122,6 @@ static PIOOFF_T io_pipe_tell(PARROT_INTERP, ARGMOD(PMC *handle))
         FUNC_MODIFIES(*handle);
 
 static size_t io_pipe_total_size(PARROT_INTERP, ARGIN(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static INTVAL io_pipe_write_b(PARROT_INTERP,
@@ -141,8 +134,7 @@ static INTVAL io_pipe_write_b(PARROT_INTERP,
         FUNC_MODIFIES(*handle);
 
 #define ASSERT_ARGS_io_pipe_adv_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_close __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -153,14 +145,12 @@ static INTVAL io_pipe_write_b(PARROT_INTERP,
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_get_flags __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_get_piohandle __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_get_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_is_eof __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -180,20 +170,16 @@ static INTVAL io_pipe_write_b(PARROT_INTERP,
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_set_eof __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_set_flags __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_set_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_tell __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_total_size __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_pipe_write_b __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle) \
@@ -332,7 +318,7 @@ io_pipe_is_eof(PARROT_INTERP, ARGMOD(PMC *handle))
 }
 
 static void
-io_pipe_set_eof(PARROT_INTERP, ARGMOD(PMC *handle), INTVAL is_set)
+io_pipe_set_eof(SHIM_INTERP, ARGMOD(PMC *handle), INTVAL is_set)
 {
     ASSERT_ARGS(io_pipe_set_eof)
     if (is_set)
@@ -394,7 +380,7 @@ Pipes don't keep track of position. Ignore.
 */
 
 static void
-io_pipe_adv_position(PARROT_INTERP, ARGMOD(PMC *handle), size_t offset)
+io_pipe_adv_position(SHIM_INTERP, ARGMOD(PMC *handle), size_t offset)
 {
     ASSERT_ARGS(io_pipe_adv_position)
     UNUSED(handle);
@@ -414,7 +400,7 @@ Pipes don't keep track of position. Ignore.
 */
 
 static void
-io_pipe_set_position(PARROT_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
+io_pipe_set_position(SHIM_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
 {
     ASSERT_ARGS(io_pipe_set_position)
     UNUSED(handle);
@@ -433,9 +419,10 @@ Pipes don't keep track of position. Return 0.
 */
 
 static PIOOFF_T
-io_pipe_get_position(PARROT_INTERP, ARGMOD(PMC *handle))
+io_pipe_get_position(SHIM_INTERP, ARGMOD(PMC *handle))
 {
     ASSERT_ARGS(io_pipe_get_position)
+    UNUSED(handle);
     /* Pipes don't keep track of file position internally. Return 0 */
     return (PIOOFF_T)0;
 }
@@ -577,7 +564,7 @@ Set flags on the Pipe.
 */
 
 static void
-io_pipe_set_flags(PARROT_INTERP, ARGIN(PMC *handle), INTVAL flags)
+io_pipe_set_flags(SHIM_INTERP, ARGIN(PMC *handle), INTVAL flags)
 {
     ASSERT_ARGS(io_pipe_set_flags)
     PARROT_FILEHANDLE(handle)->flags = flags;
@@ -594,7 +581,7 @@ Get the flags from the pipe.
 */
 
 static INTVAL
-io_pipe_get_flags(PARROT_INTERP, ARGIN(PMC *handle))
+io_pipe_get_flags(SHIM_INTERP, ARGIN(PMC *handle))
 {
     ASSERT_ARGS(io_pipe_get_flags)
     return PARROT_FILEHANDLE(handle)->flags;
@@ -611,9 +598,10 @@ Pipes have an unknown total size.
 */
 
 static size_t
-io_pipe_total_size(PARROT_INTERP, ARGIN(PMC *handle))
+io_pipe_total_size(SHIM_INTERP, ARGIN(PMC *handle))
 {
     ASSERT_ARGS(io_pipe_total_size)
+    UNUSED(handle);
     return PIO_UNKNOWN_SIZE;
 }
 
diff --git a/src/io/socket.c b/src/io/socket.c
index b65ee26dca..5e840638cb 100644
--- a/src/io/socket.c
+++ b/src/io/socket.c
@@ -1,5 +1,5 @@
 /*
-Copyright (C) 2001-2011, Parrot Foundation.
+Copyright (C) 2001-2014, Parrot Foundation.
 
 =head1 NAME
 
@@ -33,7 +33,6 @@ This file implements the Socket IO_VTABLE and some helper routines.
 static void io_socket_adv_position(PARROT_INTERP,
     ARGMOD(PMC *handle),
     size_t offset)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -43,7 +42,6 @@ static INTVAL io_socket_close(PARROT_INTERP, ARGMOD(PMC *handle))
         FUNC_MODIFIES(*handle);
 
 static INTVAL io_socket_flush(PARROT_INTERP, ARGMOD(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -55,7 +53,6 @@ static const STR_VTABLE * io_socket_get_encoding(PARROT_INTERP,
         __attribute__nonnull__(2);
 
 static INTVAL io_socket_get_flags(PARROT_INTERP, ARGIN(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static PIOHANDLE io_socket_get_piohandle(PARROT_INTERP, ARGIN(PMC *handle))
@@ -63,7 +60,6 @@ static PIOHANDLE io_socket_get_piohandle(PARROT_INTERP, ARGIN(PMC *handle))
         __attribute__nonnull__(2);
 
 static PIOOFF_T io_socket_get_position(PARROT_INTERP, ARGMOD(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -116,13 +112,11 @@ static void io_socket_set_eof(PARROT_INTERP,
 static void io_socket_set_flags(PARROT_INTERP,
     ARGIN(PMC *handle),
     INTVAL flags)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static void io_socket_set_position(PARROT_INTERP,
     ARGMOD(PMC *handle),
     PIOOFF_T pos)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -145,26 +139,22 @@ static INTVAL io_socket_write_b(PARROT_INTERP,
         FUNC_MODIFIES(*handle);
 
 #define ASSERT_ARGS_io_socket_adv_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_close __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_flush __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_get_encoding __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_get_flags __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_get_piohandle __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_get_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_is_eof __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -187,11 +177,9 @@ static INTVAL io_socket_write_b(PARROT_INTERP,
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_set_flags __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_set_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_socket_tell __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -297,9 +285,10 @@ Flush the socket. Currently this does nothing.
 */
 
 static INTVAL
-io_socket_flush(PARROT_INTERP, ARGMOD(PMC *handle))
+io_socket_flush(SHIM_INTERP, ARGMOD(PMC *handle))
 {
     ASSERT_ARGS(io_socket_flush)
+    UNUSED(handle)
     /* TODO: Do we need to fsync the socket? */
     return 0;
 }
@@ -399,7 +388,7 @@ Do nothing. Sockets don't keep track of position.
 */
 
 static void
-io_socket_adv_position(PARROT_INTERP, ARGMOD(PMC *handle), size_t offset)
+io_socket_adv_position(SHIM_INTERP, ARGMOD(PMC *handle), size_t offset)
 {
     ASSERT_ARGS(io_socket_adv_position)
     UNUSED(handle)
@@ -408,7 +397,7 @@ io_socket_adv_position(PARROT_INTERP, ARGMOD(PMC *handle), size_t offset)
 }
 
 static void
-io_socket_set_position(PARROT_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
+io_socket_set_position(SHIM_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
 {
     ASSERT_ARGS(io_socket_set_position)
     UNUSED(handle)
@@ -417,9 +406,10 @@ io_socket_set_position(PARROT_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
 }
 
 static PIOOFF_T
-io_socket_get_position(PARROT_INTERP, ARGMOD(PMC *handle))
+io_socket_get_position(SHIM_INTERP, ARGMOD(PMC *handle))
 {
     ASSERT_ARGS(io_socket_get_position)
+    UNUSED(handle)
     /* Socket doesn't keep track of position internally. Return 0 */
     return (PIOOFF_T)0;
 }
@@ -441,9 +431,10 @@ io_socket_open(PARROT_INTERP, ARGMOD(PMC *handle), ARGIN(STRING *path),
 {
     ASSERT_ARGS(io_socket_open)
     PIOHANDLE os_handle;
-    GETATTR_Socket_os_handle(interp, handle, os_handle);
+    UNUSED(path);
     UNUSED(flags);
     UNUSED(mode);
+    GETATTR_Socket_os_handle(interp, handle, os_handle);
     return Parrot_io_internal_flush(interp, os_handle);
 }
 
@@ -506,17 +497,19 @@ Return C<PIO_F_WRITE | PIO_F_READ>. Sockets are always flagged r/w.
 */
 
 static void
-io_socket_set_flags(PARROT_INTERP, ARGIN(PMC *handle), INTVAL flags)
+io_socket_set_flags(SHIM_INTERP, ARGIN(PMC *handle), INTVAL flags)
 {
     ASSERT_ARGS(io_socket_set_flags)
+    UNUSED(handle)
     UNUSED(flags)
     /* Ignore, for now */
 }
 
 static INTVAL
-io_socket_get_flags(PARROT_INTERP, ARGIN(PMC *handle))
+io_socket_get_flags(SHIM_INTERP, ARGIN(PMC *handle))
 {
     ASSERT_ARGS(io_socket_get_flags)
+    UNUSED(handle)
     /* For now, just say that all sockets are read/write handles */
     return PIO_F_WRITE | PIO_F_READ;
 }
diff --git a/src/io/stringhandle.c b/src/io/stringhandle.c
index 5e9b0c5ee4..cdfd05287f 100644
--- a/src/io/stringhandle.c
+++ b/src/io/stringhandle.c
@@ -1,5 +1,5 @@
 /*
-Copyright (C) 2001-2012, Parrot Foundation.
+Copyright (C) 2001-2014, Parrot Foundation.
 
 =head1 NAME
 
@@ -31,7 +31,6 @@ The StringHandle IO_VTABLE and helper methods.
 static void io_stringhandle_adv_position(PARROT_INTERP,
     ARGMOD(PMC *handle),
     size_t offset)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -53,7 +52,6 @@ static const STR_VTABLE * io_stringhandle_get_encoding(PARROT_INTERP,
         __attribute__nonnull__(2);
 
 static INTVAL io_stringhandle_get_flags(PARROT_INTERP, ARGIN(PMC *handle))
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static PIOHANDLE io_stringhandle_get_piohandle(PARROT_INTERP,
@@ -116,13 +114,11 @@ static void io_stringhandle_set_eof(PARROT_INTERP,
 static void io_stringhandle_set_flags(PARROT_INTERP,
     ARGIN(PMC *handle),
     INTVAL flags)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2);
 
 static void io_stringhandle_set_position(PARROT_INTERP,
     ARGMOD(PMC *handle),
     PIOOFF_T pos)
-        __attribute__nonnull__(1)
         __attribute__nonnull__(2)
         FUNC_MODIFIES(*handle);
 
@@ -145,8 +141,7 @@ static INTVAL io_stringhandle_write_b(PARROT_INTERP,
         FUNC_MODIFIES(*handle);
 
 #define ASSERT_ARGS_io_stringhandle_adv_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_stringhandle_close __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -157,8 +152,7 @@ static INTVAL io_stringhandle_write_b(PARROT_INTERP,
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_stringhandle_get_flags __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_stringhandle_get_piohandle __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -187,11 +181,9 @@ static INTVAL io_stringhandle_write_b(PARROT_INTERP,
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_stringhandle_set_flags __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_stringhandle_set_position __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
-       PARROT_ASSERT_ARG(interp) \
-    , PARROT_ASSERT_ARG(handle))
+       PARROT_ASSERT_ARG(handle))
 #define ASSERT_ARGS_io_stringhandle_tell __attribute__unused__ int _ASSERT_ARGS_CHECK = (\
        PARROT_ASSERT_ARG(interp) \
     , PARROT_ASSERT_ARG(handle))
@@ -453,7 +445,7 @@ Fall back to io_stringhandle_tell;
 */
 
 static void
-io_stringhandle_adv_position(PARROT_INTERP, ARGMOD(PMC *handle), size_t offset)
+io_stringhandle_adv_position(SHIM_INTERP, ARGMOD(PMC *handle), size_t offset)
 {
     ASSERT_ARGS(io_stringhandle_adv_position)
     UNUSED(handle)
@@ -462,7 +454,7 @@ io_stringhandle_adv_position(PARROT_INTERP, ARGMOD(PMC *handle), size_t offset)
 }
 
 static void
-io_stringhandle_set_position(PARROT_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
+io_stringhandle_set_position(SHIM_INTERP, ARGMOD(PMC *handle), PIOOFF_T pos)
 {
     ASSERT_ARGS(io_stringhandle_set_position)
     UNUSED(handle)
@@ -601,14 +593,14 @@ Get the flags from the StringHandle.
 */
 
 static void
-io_stringhandle_set_flags(PARROT_INTERP, ARGIN(PMC *handle), INTVAL flags)
+io_stringhandle_set_flags(SHIM_INTERP, ARGIN(PMC *handle), INTVAL flags)
 {
     ASSERT_ARGS(io_stringhandle_set_flags)
     PARROT_STRINGHANDLE(handle)->flags = flags;
 }
 
 static INTVAL
-io_stringhandle_get_flags(PARROT_INTERP, ARGIN(PMC *handle))
+io_stringhandle_get_flags(SHIM_INTERP, ARGIN(PMC *handle))
 {
     ASSERT_ARGS(io_stringhandle_get_flags)
     return PARROT_STRINGHANDLE(handle)->flags;