diff --git a/src/maybe_threads.h b/src/maybe_threads.h
new file mode 100644
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+++ b/src/maybe_threads.h
@@ -0,0 +1,54 @@
+// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
+// Copyright (c) 2005, Google Inc.
+// 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.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+// 
+// 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.
+
+// ---
+// Author: Paul Menage <opensource@google.com>
+
+//-------------------------------------------------------------------
+// Some wrappers for pthread functions so that we can be LD_PRELOADed
+// against non-pthreads apps.
+//-------------------------------------------------------------------
+
+#ifndef GOOGLE_MAYBE_THREADS_H_
+#define GOOGLE_MAYBE_THREADS_H_
+
+#ifdef HAVE_PTHREAD
+#include <pthread.h>
+#endif
+
+int perftools_pthread_key_create(pthread_key_t *key,
+                                 void (*destr_function) (void *));
+int perftools_pthread_key_delete(pthread_key_t key);
+void *perftools_pthread_getspecific(pthread_key_t key);
+int perftools_pthread_setspecific(pthread_key_t key, void *val);
+int perftools_pthread_once(pthread_once_t *ctl,
+                           void  (*init_routine) (void));
+
+#endif  /* GOOGLE_MAYBE_THREADS_H_ */