Problem with writing an interface for system() call...

haynes george hmg_u at yahoo.co.in
Mon Jan 9 16:58:24 CET 2006


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 at fosters:~/python]
whaaaaattttt????

any idea? 

thnks

Haynes Mathew


Send instant messages to your online friends http://in.messenger.yahoo.com 



More information about the Python-list mailing list