diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 90f595c..c6b2d32 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -253,6 +253,8 @@
 int dprintf(int, const char * __restrict, ...) __printflike(2, 3);
 int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
 
+int fdprintf(int, const char * __restrict, ...) __printflike(2, 3); /* Note: this is only in the preview release. */
+
 #ifndef __AUDIT__
 char* gets(char*) __warnattr("gets is very unsafe; consider using fgets");
 int sprintf(char* __restrict, const char* __restrict, ...)
diff --git a/libc/include/sys/atomics.h b/libc/include/sys/atomics.h
new file mode 100644
index 0000000..3366f0e
--- /dev/null
+++ b/libc/include/sys/atomics.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef _SYS_ATOMICS_H
+#define _SYS_ATOMICS_H
+
+#include <sys/cdefs.h>
+#include <sys/time.h>
+
+/* Note: this is only in the preview release. */
+
+__BEGIN_DECLS
+
+#define __ATOMIC_INLINE__ static __inline__ __attribute__((always_inline))
+
+__ATOMIC_INLINE__ int
+__atomic_cmpxchg(int old_value, int new_value, volatile int* ptr)
+{
+    /* We must return 0 on success */
+    return __sync_val_compare_and_swap(ptr, old_value, new_value) != old_value;
+}
+
+__ATOMIC_INLINE__ int
+__atomic_swap(int new_value, volatile int *ptr)
+{
+    int old_value;
+    do {
+        old_value = *ptr;
+    } while (__sync_val_compare_and_swap(ptr, old_value, new_value) != old_value);
+    return old_value;
+}
+
+__ATOMIC_INLINE__ int
+__atomic_dec(volatile int *ptr)
+{
+  return __sync_fetch_and_sub (ptr, 1);
+}
+
+__ATOMIC_INLINE__ int
+__atomic_inc(volatile int *ptr)
+{
+  return __sync_fetch_and_add (ptr, 1);
+}
+
+
+__END_DECLS
+
+#endif /* _SYS_ATOMICS_H */