C++ & Python 多线程笔记

C++¶

Posix多线程¶

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>

#include <vector>

using std::vector;

void* Proc(void* arg)
{
    pthread_t pthread = *(pthread_t *)arg;
    printf("this is thread %ld\n", pthread);
}

int main(int argc, char** argv)
{
    if (argc != 2)
    {
        printf("usage:%s thread_num", argv[0]);
        return 1;
    }
    int thread_num = atoi(argv[1]);
    vector<pthread_t> threads(thread_num);
    for (int i = 0; i < thread_num; ++i)
    {
        pthread_t pthread;
        pthread_create(&pthread, NULL, &Proc, &threads[i]);
        threads[i] = pthread;
    }
    for (vector<pthread_t>::iterator it = threads.begin(); it != threads.end(); ++it)
    {
        pthread_join(*it, NULL);
    }
    return 0;
}

boost多线程¶

1. 全局函数作为线程函数

   #include <stdio.h>
   #include <stdlib.h>
   #include <pthread.h>
   
   #include <vector>
   #include <string>
   
   #include <boost/thread.hpp>
   
   using std::vector;
   using std::string;
   
   void Proc(int num, const string& str)
   {
       printf("this is thread %d, say %s\n", num, str.c_str());
   }
   
   int main(int argc, char** argv)
   {
       if (argc != 2)
       {
           printf("usage:%s thread_num", argv[0]);
           return 1;
       }
       int thread_num = atoi(argv[1]);
       vector<boost::thread*> threads;
       for (int i = 0; i < thread_num; ++i)
       {
           boost::thread* thread = new boost::thread(&Proc, i, "Hello World!");
           threads.push_back(thread);    
       }
       for (vector<boost::thread*>::iterator it = threads.begin(); it != threads.end(); ++it)
       {
           (*it)->join();
       }
       return 0;
   }
   

2. 类成员函数作为线程函数

   #include <stdio.h>
   #include <stdlib.h>
   #include <pthread.h>
   
   #include <vector>
   #include <string>
   
   #include <boost/thread.hpp>
   #include <boost/bind.hpp>
   
   using std::vector;
   using std::string;
   
   class Test
   {
   public:
       void Proc(int num, const string& str)
       {
           printf("this is thread %d, say %s\n", num, str.c_str());
       }
   };
   
   int main(int argc, char** argv)
   {
       if (argc != 2)
       {
           printf("usage:%s thread_num", argv[0]);
           return 1;
       }
       int thread_num = atoi(argv[1]);
       vector<boost::thread*> threads;
       for (int i = 0; i < thread_num; ++i)
       {
           Test* test = new Test();
           boost::thread* thread = new boost::thread(boost::bind(&Test::Proc, test, i, "Hello World!"));
           threads.push_back(thread);    
       }
       for (vector<boost::thread*>::iterator it = threads.begin(); it != threads.end(); ++it)
       {
           (*it)->join();
       }
       return 0;
   }
   

Python¶

使用threading模块¶

import sys
import threading

def proc(num, str):
    print 'this is thread %d, say %s' % (num, str)

def start_threads(thread_num):
    threads = []
    for i in range(thread_num):
        thread = threading.Thread(target=proc, args=(i, "Hello World!"))
        threads.append(thread)
        thread.start()

    for thread in threads:
        thread.join()

if __name__ == '__main__':
    if len(sys.argv) != 2:
        print "usage:%s thread_num" % sys.argv[0]
        sys.exit(1)
    start_threads(int(sys.argv[1]))

使用multiprocessing模块¶

import sys
from multiprocessing.dummy import Pool as ThreadPool

def proc(arg):
    num, str = arg
    print 'this is thread %d, say %s' % (num, str)

def start_threads(thread_num):
    pool = ThreadPool(thread_num)
    args = [(i, "Hello World!") for i in range(thread_num)]
    pool.map(proc, args)
    pool.close()
    pool.join()

if __name__ == '__main__':
    if len(sys.argv) != 2:
        print "usage:%s thread_num" % sys.argv[0]
        sys.exit(1)
    start_threads(int(sys.argv[1]))