tests/test-progs/pthread/src/test_std_thread.cpp

/*
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  * from this software without specific prior written permission.
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  * 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
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  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
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  *
  * Authors: Moyang Wang
  */

#include <cstdlib>
#include <iostream>
#include <string>
#include <thread>
#include <vector>

//------------------------------------------------------------------------
// Test std::thread
//------------------------------------------------------------------------
// Create n threads, run them in parallel and wait for them in the master
// thread.
// Each child thread writes its thread id to an output array

#define MAX_N_WORKER_THREADS 10

int main( int argc, char* argv[] )
{
    int n_worker_threads = 0;

    std::vector< std::thread > threads;
    std::vector<int> outputs( MAX_N_WORKER_THREADS, 0 );

    for ( int tid = 0; tid < MAX_N_WORKER_THREADS; ++tid ) {
        try {
            threads.push_back( std::thread( [&] (size_t thread_id ) {
                        std::cout << "Hello from thread " <<  thread_id
                                  << std::endl;
                        outputs[thread_id] = thread_id;
                    }, tid ) );
        } catch ( const std::system_error& err ) {
            break;
        }
        n_worker_threads++;
    }

    std::cout << "Hello from master thread" << std::endl;

    // sync up all threads
    for (int i = 0; i < n_worker_threads; ++i) {
        threads[i].join();
    }

    if (n_worker_threads < 1) {
        return EXIT_FAILURE;
    }

    for ( int i = 0; i < n_worker_threads; ++i ) {
        if ( outputs[i] != i ) {
            return EXIT_FAILURE;
        }
    }

    return EXIT_SUCCESS;
}