3 files changed, 63 insertions, 0 deletions
diff --git a/libio/Versions b/libio/Versions
index 654ca29a89..1fbc313cb9 100644
--- a/libio/Versions
+++ b/libio/Versions
@@ -104,6 +104,10 @@ libc {
     # functions used in libstdc++
     _IO_fgetpos; _IO_fgetpos64; _IO_fsetpos; _IO_fsetpos64;
 
+    # LinuxThreads uses this protected interface
+    _IO_iter_begin; _IO_iter_end; _IO_iter_next; _IO_iter_file;
+    _IO_list_lock; _IO_list_unlock; _IO_list_resetlock;
+
     # f*
     fgetpos; fgetpos64; fgetwc; fgetwc_unlocked; fgetws; fgetws_unlocked;
     fputwc; fputwc_unlocked; fputws; fputws_unlocked; fsetpos; fsetpos64;
diff --git a/libio/genops.c b/libio/genops.c
index c59518143f..fb4f08bd3f 100644
--- a/libio/genops.c
+++ b/libio/genops.c
@@ -1028,6 +1028,50 @@ _IO_default_imbue (fp, locale)
 {
 }
 
+_IO_ITER
+_IO_iter_begin()
+{
+  return _IO_list_all;
+}
+
+_IO_ITER
+_IO_iter_end()
+{
+	return NULL;
+}
+
+_IO_ITER
+_IO_iter_next(iter)
+    _IO_ITER iter;
+{
+  return iter->_chain;
+}
+
+_IO_FILE *
+_IO_iter_file(iter)
+    _IO_ITER iter;
+{
+  return iter;
+}
+
+void
+_IO_list_lock()
+{
+  _IO_lock_lock (list_all_lock);
+}
+
+void
+_IO_list_unlock()
+{
+    _IO_lock_unlock (list_all_lock);
+}
+
+void
+_IO_list_resetlock()
+{
+  _IO_lock_init (list_all_lock);
+}
+
 
 #ifdef TODO
 #if defined(linux)
diff --git a/libio/libioP.h b/libio/libioP.h
index 59d20cd4be..090f98a02d 100644
--- a/libio/libioP.h
+++ b/libio/libioP.h
@@ -313,6 +313,10 @@ struct _IO_FILE_plus
   const struct _IO_jump_t *vtable;
 };
 
+/* Iterator type for walking global linked list of _IO_FILE objects. */
+
+typedef _IO_FILE *_IO_ITER;
+
 /* Generic functions */
 
 extern void _IO_switch_to_main_get_area __P ((_IO_FILE *));
@@ -351,6 +355,17 @@ extern int _IO_wmarker_delta __P ((struct _IO_marker *));
 extern int _IO_seekmark __P ((_IO_FILE *, struct _IO_marker *, int));
 extern int _IO_seekwmark __P ((_IO_FILE *, struct _IO_marker *, int));
 
+/* Functions for iterating global list and dealing with
+   its lock */
+
+extern _IO_ITER _IO_iter_begin __P ((void));
+extern _IO_ITER _IO_iter_end __P ((void));
+extern _IO_ITER _IO_iter_next __P ((_IO_ITER));
+extern _IO_FILE *_IO_iter_file __P ((_IO_ITER));
+extern void _IO_list_lock __P ((void));
+extern void _IO_list_unlock __P ((void));
+extern void _IO_list_resetlock __P ((void));
+
 /* Default jumptable functions. */
 
 extern int _IO_default_underflow __P ((_IO_FILE *));