diff --git a/libc/bionic/ptrace.cpp b/libc/bionic/ptrace.cpp
new file mode 100644
index 0000000..c0fd5de
--- /dev/null
+++ b/libc/bionic/ptrace.cpp
@@ -0,0 +1,67 @@
+/*
+ * 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.
+ */
+
+#include <sys/types.h>
+#include <sys/ptrace.h>
+
+extern "C" long __ptrace(int request, pid_t pid, void* addr, void* data);
+
+long ptrace(int request, pid_t pid, void* addr, void* data) {
+  switch (request) {
+    case PTRACE_PEEKUSR:
+    case PTRACE_PEEKTEXT:
+    case PTRACE_PEEKDATA:
+      {
+      long word;
+      long ret = __ptrace(request, pid, addr, &word);
+      if (ret == 0) {
+        return word;
+      } else {
+        // __ptrace already set errno for us.
+        return -1;
+      }
+    }
+
+    default:
+      return __ptrace(request, pid, addr, data);
+  }
+}
+
+/*
+ * Hook for gdb to get notified when a thread is created
+ */
+#ifdef __i386__
+#define ATTRIBUTES __attribute__((noinline)) __attribute__((fastcall))
+#else
+#define ATTRIBUTES __attribute__((noinline))
+#endif
+
+extern "C" void _thread_created_hook(pid_t) ATTRIBUTES;
+
+void _thread_created_hook(pid_t) {
+}