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diff --git a/3rdparty/asio/src/examples/cpp03/spawn/parallel_grep.cpp b/3rdparty/asio/src/examples/cpp03/spawn/parallel_grep.cpp
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+//
+// parallel_grep.cpp
+// ~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#include <asio/dispatch.hpp>
+#include <asio/post.hpp>
+#include <asio/spawn.hpp>
+#include <asio/strand.hpp>
+#include <asio/thread_pool.hpp>
+#include <boost/bind.hpp>
+#include <fstream>
+#include <iostream>
+#include <string>
+
+using asio::dispatch;
+using asio::spawn;
+using asio::strand;
+using asio::thread_pool;
+using asio::yield_context;
+
+void print_match(std::string input_file, std::string line)
+{
+ std::cout << input_file << ':' << line << std::endl;
+}
+
+void search_file(std::string search_string, std::string input_file,
+ strand<thread_pool::executor_type> output_strand, yield_context yield)
+{
+ std::ifstream is(input_file.c_str());
+ std::string line;
+ std::size_t line_num = 0;
+ while (std::getline(is, line))
+ {
+ // If we find a match, send a message to the output.
+ if (line.find(search_string) != std::string::npos)
+ {
+ dispatch(output_strand, boost::bind(&print_match, input_file, line));
+ }
+
+ // Every so often we yield control to another coroutine.
+ if (++line_num % 10 == 0)
+ post(yield);
+ }
+}
+
+int main(int argc, char* argv[])
+{
+ try
+ {
+ if (argc < 2)
+ {
+ std::cerr << "Usage: parallel_grep <string> <files...>\n";
+ return 1;
+ }
+
+ // We use a fixed size pool of threads for reading the input files. The
+ // number of threads is automatically determined based on the number of
+ // CPUs available in the system.
+ thread_pool pool;
+
+ // To prevent the output from being garbled, we use a strand to synchronise
+ // printing.
+ strand<thread_pool::executor_type> output_strand(pool.get_executor());
+
+ // Spawn a new coroutine for each file specified on the command line.
+ std::string search_string = argv[1];
+ for (int argn = 2; argn < argc; ++argn)
+ {
+ std::string input_file = argv[argn];
+ spawn(pool, boost::bind(&search_file,
+ search_string, input_file, output_strand, _1));
+ }
+
+ // Join the thread pool to wait for all the spawned tasks to complete.
+ pool.join();
+ }
+ catch (std::exception& e)
+ {
+ std::cerr << "Exception: " << e.what() << "\n";
+ }
+
+ return 0;
+}