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diff --git a/test/util/thread_util.h b/test/util/thread_util.h
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+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef GVISOR_TEST_UTIL_THREAD_UTIL_H_
+#define GVISOR_TEST_UTIL_THREAD_UTIL_H_
+
+#include <pthread.h>
+#ifdef __linux__
+#include <sys/syscall.h>
+#endif
+#include <unistd.h>
+
+#include <functional>
+#include <utility>
+
+#include "test/util/logging.h"
+
+namespace gvisor {
+namespace testing {
+
+// ScopedThread is a minimal wrapper around pthreads.
+//
+// This is used in lieu of more complex mechanisms because it provides very
+// predictable behavior (no messing with timers, etc.) The thread will
+// automatically joined when it is destructed (goes out of scope), but can be
+// joined manually as well.
+class ScopedThread {
+ public:
+  // Constructs a thread that executes f exactly once.
+  explicit ScopedThread(std::function<void*()> f) : f_(std::move(f)) {
+    CreateThread();
+  }
+
+  explicit ScopedThread(const std::function<void()>& f) {
+    f_ = [=] {
+      f();
+      return nullptr;
+    };
+    CreateThread();
+  }
+
+  ScopedThread(const ScopedThread& other) = delete;
+  ScopedThread& operator=(const ScopedThread& other) = delete;
+
+  // Joins the thread.
+  ~ScopedThread() { Join(); }
+
+  // Waits until this thread has finished executing. Join is idempotent and may
+  // be called multiple times, however Join itself is not thread-safe.
+  void* Join() {
+    if (!joined_) {
+      TEST_PCHECK(pthread_join(pt_, &retval_) == 0);
+      joined_ = true;
+    }
+    return retval_;
+  }
+
+ private:
+  void CreateThread() {
+    TEST_PCHECK_MSG(pthread_create(
+                        &pt_, /* attr = */ nullptr,
+                        +[](void* arg) -> void* {
+                          return static_cast<ScopedThread*>(arg)->f_();
+                        },
+                        this) == 0,
+                    "thread creation failed");
+  }
+
+  std::function<void*()> f_;
+  pthread_t pt_;
+  bool joined_ = false;
+  void* retval_ = nullptr;
+};
+
+#ifdef __linux__
+inline pid_t gettid() { return syscall(SYS_gettid); }
+#endif
+
+}  // namespace testing
+}  // namespace gvisor
+
+#endif  // GVISOR_TEST_UTIL_THREAD_UTIL_H_