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我正在 Windows 上使用一些 C++ 来启动 python.exe (2.7) 并使用 stdin、stdout 和 stderr 与之交互。我正在使用 Visual Studio 2015、Boost 1.59 和 Boost Process 0.5。

我通过设置命令行来成功启动 python.exe，例如“python -c”print 'hello world'”，并且标准输出捕获“hello world”。

这是代码：

#include <boost/process.hpp>
#include <boost/iostreams/device/file_descriptor.hpp>
#include <boost/iostreams/stream.hpp>
#include <boost/iostreams/tee.hpp>
#include <boost/iostreams/filtering_stream.hpp>
#include <iostream>
#include <fstream>

namespace bp = boost::process;
namespace io = boost::iostreams;
using namespace bp;
using namespace bp::initializers;

bp::pipe create_async_pipe(std::string desc)
{
#if defined(BOOST_WINDOWS_API)
    std::string name = "\\\\.\\pipe\\boost_process_async_io\\" + desc;
    HANDLE handle1 = ::CreateNamedPipeA(name.c_str(), PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED, 0, 1, 8192, 8192, 0, NULL);
    HANDLE handle2 = ::CreateFileA(name.c_str(), GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL);
    return make_pipe(handle1, handle2);
#elif defined(BOOST_POSIX_API)
    return create_pipe();
#endif
}

int main()
{
    bp::pipe pIn = create_async_pipe("stdout");
    //bp::pipe pOut = create_async_pipe("stdin");
    {
        //io::file_descriptor_sink stdout_sink("C:\\WA\\output.txt");
        io::file_descriptor_sink stdout_sink(pIn.sink, io::close_handle);
        //io::file_descriptor_source stdin_source(pOut.source, io::close_handle);
        bp::child c = execute(
            run_exe("C:\\Python27\\python.exe"),
            set_cmd_line(L"python -c \"print 'hello world'\""),
            bind_stdout(stdout_sink),
            bind_stderr(stdout_sink)//,
            //bind_stdin(stdin_source)
            );
    }

    io::file_descriptor_source stdout_source(pIn.source, io::close_handle);
    //io::file_descriptor_sink stdin_sink(pOut.sink, io::close_handle);

    io::stream<io::file_descriptor_source> is(stdout_source);
    //io::stream<io::file_descriptor_sink> os(stdin_sink);

    //os << "print 'hello world'\r\nexit()\r\n";

    std::string output;
    std::getline(is, output);
    std::cout << output << std::endl;   
}

如果我删除 set_cmd_line() 或将字符串更改为 L“python”，我希望 Python 启动到交互模式，就像我从命令行执行“python.exe”一样。

该代码在这里：

#include <boost/process.hpp>
#include <boost/iostreams/device/file_descriptor.hpp>
#include <boost/iostreams/stream.hpp>
#include <boost/iostreams/tee.hpp>
#include <boost/iostreams/filtering_stream.hpp>
#include <iostream>
#include <fstream>

namespace bp = boost::process;
namespace io = boost::iostreams;
using namespace bp;
using namespace bp::initializers;

bp::pipe create_async_pipe(std::string desc)
{
#if defined(BOOST_WINDOWS_API)
    std::string name = "\\\\.\\pipe\\boost_process_async_io\\" + desc;
    HANDLE handle1 = ::CreateNamedPipeA(name.c_str(), PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED, 0, 1, 8192, 8192, 0, NULL);
    HANDLE handle2 = ::CreateFileA(name.c_str(), GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL);
    return make_pipe(handle1, handle2);
#elif defined(BOOST_POSIX_API)
    return create_pipe();
#endif
}

int main()
{
    bp::pipe pIn = create_async_pipe("stdout");
    //bp::pipe pOut = create_async_pipe("stdin");
    {
        //io::file_descriptor_sink stdout_sink("C:\\WA\\output.txt");
        io::file_descriptor_sink stdout_sink(pIn.sink, io::close_handle);
        //io::file_descriptor_source stdin_source(pOut.source, io::close_handle);
        bp::child c = execute(
            run_exe("C:\\Python27\\python.exe"),
            **//set_cmd_line(L"python -c \"print 'hello world'\""),**
            bind_stdout(stdout_sink),
            bind_stderr(stdout_sink)//,
            //bind_stdin(stdin_source)
            );
    }

    io::file_descriptor_source stdout_source(pIn.source, io::close_handle);
    //io::file_descriptor_sink stdin_sink(pOut.sink, io::close_handle);

    io::stream<io::file_descriptor_source> is(stdout_source);
    //io::stream<io::file_descriptor_sink> os(stdin_sink);

    //os << "print 'hello world'\r\nexit()\r\n";

    std::string output;
    std::getline(is, output);
    std::cout << output << std::endl;   
}

当我运行第二个示例时，python 将暂时运行，然后关闭。

这个程序的一些背景。我想创建一个 Python 记录器，它逐行读取 Python 文件，并逐行执行它，就好像它是在解释器中编写的一样。因此，会有如下代码：

pyChild.waitForPrompt();             // Waits for >>>, >>?, ..., etc.
pyChild.write("print 'hello world'); // >>> print 'hello world'
std::cout << pyChild.readLine();     // hello world

我与 boost 无关，我尝试过其他选项，例如 Poco 和MSDN Windows 示例，但没有成功。

当然，在正确传输标准输出/标准错误后，标准输入也将正常工作。我也试图让它发挥作用，但失败了。

提前致谢！

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1 回答 1

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也许为时已晚......但它对我有用 -i 和 -u 选项：Using boost 1.69, python 3.7

//create synchronous pipe streams
bp::opstream pyin;
bp::ipstream pyout;
//launch child process with the options for unbuffered std_in and out and interpreter
bp::child c("python -u -i", bp::std_in < pyin, bp::std_out > pyout);

//send py instruccions to python process and recover stdout
pyin << "print('Hello');" << endl;
string pyout_str_hello;
pyout >> pyout_str_hello;

pyin << "print('World');" << endl;
string pyout_str_world;
pyout >> pyout_str_world;

cout << pyout_str_hello << ' ' << pyout_str_world << endl;
于 2019-04-24T13:09:26.913 回答