From: "Iñaki Baz Castillo" <ibc@...>
Date: 2009-12-03T07:01:14+09:00
Subject: Re: How to use rb_enc_str_new() to create a String with UTF-8 encoding?

El Miércoles, 2 de Diciembre de 2009, Brian Candler escribió:
> Iñaki Baz Castillo wrote:
> > El Miércoles, 2 de Diciembre de 2009, Brian Candler escribió:
> >> > How should I fill the third 'enc' argument?
> >>
> >>     return rb_enc_from_index(idx);
> >> }
> >
> > Humm, it involves allocating memory for the rb_encoding object
> 
> Why? AFAICS, you can just pass a pointer to an existing encoding object.
> They are not mutated.
> 
> There are other examples, e.g. from io.c
> 
> #ifdef _WIN32
>     if (utf16 == (rb_encoding *)-1) {
>         utf16 = rb_enc_find("UTF-16LE");
>         if (utf16 == rb_ascii8bit_encoding())
>             utf16 = NULL;
>     }
>     if (utf16) {
>         VALUE wfname = rb_str_encode(fname, rb_enc_from_encoding(utf16),
> 0,
>                                      Qnil);
>         rb_enc_str_buf_cat(wfname, "", 1, utf16); /* workaround */
>         data.fname = RSTRING_PTR(wfname);
>         data.wchar = 1;
>     }
>     else {
>         data.wchar = 0;
>     }
> #endif
> 
> It looks like rb_enc_from_encoding() takes a pointer to the rb_encoding
> object returned from rb_enc_find, and turns it into a VALUE

Ok, so the rb_encoding objects already exist and I just must use a point to 
it.
Thanks a lot. 


-- 
Iñaki Baz Castillo <ibc@aliax.net>