[R] Pass String from R to C

[Duncan Murdoch]

On 25/04/2011 12:51 PM, Jaimin Dave wrote:
> I tried using char ** but it is printing some random string.

str is a pointer to an array of pointers to strings.  That's what char** 
means.  So you need to declare it that way, and use it that way.

This works for me:

File test.c:

void test(char **str)
{
   Rprintf("%s",*str);
}

Duncan Murdoch
> On Sat, Apr 23, 2011 at 6:08 PM, Duncan Murdoch<murdoch.duncan at gmail.com>wrote:
>
> >  On 11-04-23 7:04 PM, Jaimin Dave wrote:
> >
> >>  Hi,
> >>  I am using a function which accepts the string from R and prints it.
> >>  But when I am calling .C("main","hello");
> >>  it is printing any random thing.
> >>  My C function is
> >>  void main(char *str)
> >>
> >
> >  See Writing R Extensions.  The declaration should be char **str.
> >
> >  Duncan Murdoch
> >
> >   {
> >>  Rprintf("%s",str);
> >>  }
> >>
> >>  Can you help how to achieve this using .C interface?
> >>
> >>  Thanks
> >>  Jaimin
> >>
> >>         [[alternative HTML version deleted]]
> >>
> >>  ______________________________________________
> >>  R-help at r-project.org mailing list
> >>  https://stat.ethz.ch/mailman/listinfo/r-help
> >>  PLEASE do read the posting guide
> >>  http://www.R-project.org/posting-guide.html<http://www.r-project.org/posting-guide.html>
> >>  and provide commented, minimal, self-contained, reproducible code.
> >>
> >
> >
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
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> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.