Problem writing an extension for python!

tuxfood · 01-09-2006, 05:06 AM

hi ..

I was reading the tutorial "Extending and Embedding the python interpreter" available with python ..

http://www.python.org/doc/2.2.3/ext/ext.html

As per given in the tutorial i created an interface to the system() system call.

this is the code of my module

Code:

#include<Python.h>

static PyObject * spam_system(self,args)
{
	PyObject * self;
	PyObject * args;
	char * command;
	int sts;

	if ( !PyArg_ParseTuple(args, "s" , &command))
		return NULL;
	
	sts = system(command);
	return Py_BuildValue("i",sts);
}

static PyMethodDef SpamMethods[] = {
	{ "system", spam_system , METH_VARARGS,"Execute a shell command"},
	{NULL,NULL,0,NULL}
};

void initspam(void){
	(void) Py_InitModule("spam", SpamMethods);
}


int main(int argc,char **argv)
{
//	Py_SetProgName(argv[0]);

/* I COMMENTED THE ABOVE CALL AS IT GAVE ME SOME WIERD ERROR */
	
	Py_Initialize();

	initspam();
}

i was able to compile the above code using disutils package available with python .

http://www.python.org/doc/2.2.3/ext/building.html

I was even able to import the module into the python interpreter but caling the function gave me the following error

Code:

>>>import spam
>>>spam.system("ls -l")
python: Python/getargs.c:90: vgetargs1: Assertion `compat || (args != (PyObject*)((void *)0))' failed.
Aborted
[haynes@fosters:~/python]

whaaaaattttt????

any idea?

thnks

tuxfood