From: Paul Brannan <pbrannan@...>
Date: 2003-03-19T00:59:26+09:00
Subject: Re: ruby-dev summary 19773-19824

On Tue, Mar 18, 2003 at 09:35:14AM +0900, nobu.nokada@softhome.net wrote:
> Paul Brannan wrote:
> > Will rb_str2cstr be modified to use StringValuePtr(), or will extensions
> > have to change to get non-NULL C-strings from STR2CSTR in 1.8.0?  If it
> > is not modified, how should extension writers write code to work on both
> > 1.6.x and 1.8.0?
> 
> Signatures of rb_str2cstr() and StringValuePtr() are different.
> StringValuePtr() requires lvalue in order to get rid of
> possibility of dangling pointer, so extensions should change to
> use latter.

I don't understand.  Can you elaborate?

> > In what conditions will RSTRING(str)->ptr be NULL?
> 
> An example:
> 
>   ' '.dup.rstrip.gsub(/a/, '')

Why will this leave ptr NULL?  It doesn't seem very obvious from the
source (in str_gsub, ptr is set equal to buf, which is allocated with
malloc(), which should never return 0 except on error).

Paul