Pass argument to PyRun_File(***)

Question

I am writing some code in C and in Python.

I have a python file called sample.py which accepts two string parameters.

My C program calls the python function using the PyRun_SimpleString(). In this way I am not able to pass any parameters.

By PyRun_SimpleString():

int main(int argc,char *argv[])
{
 ......
PyRun_SimpleString("import sample\nsample.mainfunc("argv[1]",'Isolated_domU_t')\n");
.....
}

How can I pass parameters argv[1] by using PyRun_SimpleString(*)?

If you want to call a function why are you executing a program instead? You should import the `sample` module and call the function using `PyObject_Call*` functions. — Bakuriu, Mar 13 '14 at 14:41
It looks like you don't know how to concatenate strings in C. Please have a look at the following SO question on that matter: http://stackoverflow.com/questions/308695/c-string-concatenation — Carsten, Mar 17 '14 at 08:54

score 1 · Answer 1 · answered Aug 17 '20 at 10:17

To set arguments do like the following code:

wchar_t** wargv = new wchar_t*[argc];
for(int i = 0; i < argc; i++)
{
    wargv[i] = Py_DecodeLocale(argv[i], nullptr);
    if(wargv[i] == nullptr)
    {
        return EXIT_FAILURE;
    }
}

Py_Initialize();

// char* py=...
PySys_SetArgv(argc, wargv);
PyRun_SimpleString(py);

Py_Finalize();

for(int i = 0; i < argc; i++)
{
    PyMem_RawFree(wargv[i]);
    wargv[i] = nullptr;
}

delete[] wargv;
wargv = nullptr;

Carsten · Answer 2 · 2014-03-22T10:42:14.860

0

Use PyRun_String. It has a signature similar to PyRun_File:

PyObject* PyRun_String(const char *str, int start, PyObject *globals, PyObject *locals)

Update:

In your case, it whould be simple enough to just copy the command line arguments into the string you want to execute, just like you tried in your question. Your code won't work though, because that's not how you concatenate strings in C. Try this instead:

#include <Python.h>
#include <stdio.h>
#include <string.h>

int main(int argc, char **argv) {
    char py[1000]; /* that should be big enough */
    strcpy(py, "import sample\nsample.mainfunc(");
    strcat(py, argv[1]);
    strcat(py, ",'Isolated_domU_t')\n");

    Py_Initialize();
    PyRun_SimpleString(py);
    Py_Finalize();
}

This is, of course, only the quick&dirty version without checking if there even is an argument passed to the program, or checking for its length.

edited Mar 22 '14 at 10:42

answered Mar 13 '14 at 14:42

Carsten

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i am not getting(understood) this syntax so only i posted here. where can i get the real examples..:) – Cooldharma06 Mar 14 '14 at 04:52
The syntax is almost the same as `PyRun_File`'s. I thought you wanted a method that takes parameters similar to `PyRun_File`. – Carsten Mar 14 '14 at 05:57
http://stackoverflow.com/questions/22300349/call-python-function-in-c-code please refer this one. in that answer i changed the main to addfunction() and for that addfunction()[main] i am passing the parameters how i am can achieve that one. simply in that answer it as 42,42 instaed of that one i have to pass from command line – Cooldharma06 Mar 14 '14 at 07:05
It looks like what you want is to take arguments that you pass to your C program and pass them to your embedded python script. If that is the case, please update your question accordingly. I'll update my answer later. – Carsten Mar 14 '14 at 08:10

score 0 · Answer 3 · answered Feb 06 '18 at 18:12

can use the snprintf or like his function and type this

char haies1[2048];
snprintf(haies1, sizeof(haies1),"import sample\n"
                "sample.mainfunc("%s",'Isolated_domU_t')\n",argv[1])

then can use the PyRun_SimpleString function like this

Py_Initialize();
PyRun_SimpleString(haies1);
Py_Finalize();

Pass argument to PyRun_File(***)

3 Answers3

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