diff --git a/libc/bionic/dup.cpp b/libc/bionic/dup.cpp
new file mode 100644
index 0000000..d9e89a5
--- /dev/null
+++ b/libc/bionic/dup.cpp
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2013 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 <fcntl.h>
+#include <unistd.h>
+
+#include "private/bionic_fdtrack.h"
+
+extern "C" int __dup(int old_fd);
+extern "C" int __dup3(int old_fd, int new_fd, int flags);
+
+int dup(int old_fd) {
+  return FDTRACK_CREATE(__dup(old_fd));
+}
+
+int dup2(int old_fd, int new_fd) {
+  // If old_fd is equal to new_fd and a valid file descriptor, dup2 returns
+  // old_fd without closing it. This is not true of dup3, so we have to
+  // handle this case ourselves.
+  if (old_fd == new_fd) {
+    if (fcntl(old_fd, F_GETFD) == -1) {
+      return -1;
+    }
+    return old_fd;
+  }
+
+  return FDTRACK_CREATE(__dup3(old_fd, new_fd, 0));
+}
+
+int dup3(int old_fd, int new_fd, int flags) {
+  return FDTRACK_CREATE(__dup3(old_fd, new_fd, flags));
+}