From: "Mauricio Fernández" <batsman.geo@...>
Date: 2003-10-10T02:14:59+09:00
Subject: Re: I'm stuck

On Fri, Oct 10, 2003 at 01:15:26AM +0900, Friedrich Dominicus wrote:
> > >> /* At this step you are playing a dangerous game with the GC */
> > F> what you you mean which this step ?
> > F> ruby_init? How should I know what else to set up or use?
> > 
> >  Here a stupid example :
> > 
> >    int main(void)
> >    {
> >        char i;
> >        VALUE obj;
> >        VALUE klass;
> > 
> >        ruby_init();
> >        obj = rb_str_new2("a string");
> > 
> >        /* call some ruby functions which call the GC */
> > 
> >        i = RSTRING(obj)->ptr[0];
> > 
> >        /* there are many chances than the String referenced by obj
> >           was removed by the GC, and you have a segfault when you try
> >           to access RSTRING(obj)->ptr[0] */
> Ok I understand that now, what do I have to do that it does not
> happen? 
> 
> What's the simplest but too safe way to solve my simple problem. I
> just want the C side access the Ruby side as partly pointed out here. 

void do_stuff()
{
	char i;
	VALUE obj;
	VALUE klass;
	
	obj = rb_str_new2("a string");
	
	/* call some ruby functions which call the GC */
	
	i = RSTRING(obj)->ptr[0];
	...
}

int main(void)
{
 ruby_init();
 do_stuff();
}

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