C++调用python

本文以实例code讲解 C++ 调用 python 的方法。

本文在util.h中实现三个函数：

1. init_log: 用google log(glog)初始化log 
2. exe_command: 由 C++ 执行 shell code 
3. exe_py: C++调用python文件

---

Code:

Python:

def pr(args):
    for arg in args:
        print arg

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C++: 
include/util.h:

/***************************************************************************
 *-
 * Copyright (c) 2015 Baidu.com, Inc. All Rights Reserved
 *-
 **************************************************************************/
-
-
-
/**
 * @file util.h
 * @author zhangruiqing01([e-mail])
 * @date 2015/10/24 02:17:56
 * @version $Revision$-
 * @brief-
 *  i
 **/                                                                         

#ifndef  __UTIL_H_
#define  __UTIL_H_                                                           

#include "glog/logging.h"
#include <string>
#include <vector>                                                            

#define PYTHON_LIB_PATH "~/.jumbo/lib/python2.7"
#define PYTHON_BIN_PATH "~/.jumbo/bin/python2.7"                             

// initial log
void init_log(const char* argv);                                             

// exe shell command
char* exe_command(const char* cmd);                                          

// exe python command
void exe_py(
        const std::string module_name,
        const std::string func_name,
        const std::vector<std::string>& args);

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src/util.cpp:

/***************************************************************************
 *-
 * Copyright (c) 2015 Baidu.com, Inc. All Rights Reserved
 *-
 **************************************************************************/
-
-
-
/**
 * @file src/util.cpp
 * @author zhangruiqing01([e-mail])
 * @date 2015/10/24 02:12:34
 * @version $Revision$-
 * @brief-
 *--
 **/                                                                             

#include "util.h"
#include <stdio.h>
#include <errno.h>
#include <Python.h>
#define MAX_LENGTH 2048                                                          

void init_log(const char* argv){
    if (!getenv("GLOG_logtostderr")) {
          google::LogToStderr();
    }
    google::InstallFailureSignalHandler();
    google::InitGoogleLogging(argv);
    LOG(INFO) << "Create Log successfully";
}                                                                                

char* exe_command(const char* cmd){
    FILE* fres;
    if ((fres = popen(cmd, "r")) != NULL){
        char* buf_res = (char*) malloc(MAX_LENGTH);
        fread(buf_res, MAX_LENGTH, 1, fres);
        buf_res[strlen(buf_res) - 3] = '\0';
        //buf_res
        fprintf(stderr, "------------\nEXE RESULT: %s\n------------\n", buf_res);
        pclose(fres);
        return buf_res;
    }
    else{
        LOG(FATAL) << "Failed to execute '" << cmd << "'";
    }
}     

void exe_py(
        const std::string module_name,
        const std::string func_name,
        const std::vector<std::string>& args){
    std::string args_str = "";
    for(auto& arg : args){
        args_str += arg + ",";
    }                                                               

    std::string cmd = "LD_LIBRARY_PATH=" +
        std::string(PYTHON_LIB_PATH) + ":" + "$LD_LIBRARY_PATH " +
        std::string(PYTHON_BIN_PATH) +
        " -c 'import sys\n" +
        "sys.path.append(\"pyfiles\")\n" +
        "import " + module_name + "\n" +
        "ret = " + module_name + "." + func_name + "([" +
        args_str + "])'";
    LOG(INFO) << "exec command: "<< cmd;
    char* res = exe_command(cmd.c_str());
}

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main.cpp:

/***************************************************************************
 *-
 * Copyright (c) 2015 Baidu.com, Inc. All Rights Reserved
 *-
 **************************************************************************/
-
-
-
/**
 * @file src/util.cpp
 * @author zhangruiqing01([e-mail])
 * @date 2015/10/23 10:41:23
 * @version $Revision$-
 * @brief-
 *--
 **/                                                                                 

#include <stdio.h>
#include <vector>
#include <string>
#include <util.h>
#include <iostream>                                                                  

int main(int argc, char* argv[]){
    //initial log
    init_log(argv[0]);                                                               

    char cmd[100]="echo 'abc'";
    char* res = exe_command(cmd);                                                    

    std::string arg_v[] = {"1"};
    std::vector<std::string>py_args(arg_v, arg_v + sizeof(arg_v)/sizeof(arg_v[0]));
    exe_py("printargs", "pr", py_args);

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注意其中的Makefile文件：

1. 需要include python.h 所在目录，即python的include目录
2. C++编译参数加入-std=c++11： 
   CXXFLAGS(‘-g -pipe -W -Wall -fPIC -std=c++11’)
3. include glog所在目录

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最后看一下本文中程序的结构：

执行结果： 

 

 

from: http://blog.****.net/abcjennifer/article/details/49377123