如何在导入 `site` 模块之前运行 Python 代码？

Question

有没有办法在导入site模块之前执行 Python 代码？

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In case it matters, I'm asking because I'm running an embedded Python interpreter via Py_Initialize , and I'd like to configure the Python environment using Python code, however it's important this happens before the site module is imported since the changes impact它是如何初始化的。

Answer 1

您可以设置Py_NoSiteFlag以在初始化 Python 解释器时禁止加载site.py site可以稍后手动加载。

这是一个最小的例子：

#define PY_SSIZE_T_CLEAN
#include <Python.h>

int
main(int argc, char *argv[])
{
    Py_NoSiteFlag = 1; /* Suppress 'import site' */
    Py_Initialize();
    PyRun_SimpleString("import sys; print('site' in sys.modules)\n");

    //There are no site-packages in path:
    PyRun_SimpleString("print(sys.path)\n");

    // do what must be done
    // ....

    //now, import site manually,
    //call site.main(), so site-packages are added to sys.path:
    PyRun_SimpleString("import site; site.main()");

    //now, site-packages are in path:
    PyRun_SimpleString("print(sys.path)\n");

    if (Py_FinalizeEx() < 0) {
        exit(120);
    }
    return 0;
}

运行生成的可执行文件时，会看到该site未在Py_Initialize中加载（第一行打印为False ）并稍后加载。 我们还需要显式调用site.main()以将站点包放入sys.path 。