UTF8 Encoding and Local Encoding question

[O-Zone <o-zone zerozone it>]

Hi all,
i've written a GTK Editor (ozeditor, http://ozeditor.zerozone.it) and, because 
it use a TextBuffer, i need to convert all files in UTF8. It work *but* 
sometimes g_utf8_validate write an error to strerr and not in return value of 
function. Here the piece of code:

....
    fread(buffer,ffs.st_size,1,ff);
#ifdef DEBUG
    g_print("DEBUG: Locale to UTF8\n");
#endif
    /* Converti in UTF-8 */
    bbuf = g_malloc0(ffs.st_size);
    memcpy(bbuf,buffer,ffs.st_size);
    g_free(buffer);
    buffer = g_malloc0(ffs.st_size*2);
    buffer = g_locale_to_utf8(bbuf,ffs.st_size,&bread,&bwrite,&error);
    g_free(bbuf); 
    if(error) {
        g_free(buffer);
        OzEDIT_ErrorDialog("Cannot convert %s to UFT8 :-( Error 
%s\n",filename,error->message);
        g_error_free(error);
        new_object->status = OBJECT_STATUS_NEW;
        new_object->type = OBJECT_TYPE_UNKNOWN;
        return;                 
    }
    /* File loaded, now display it */
    gtk_text_buffer_set_text(new_object->text_buffer,buffer,-1);
    gtk_text_buffer_set_modified(new_object->text_buffer,FALSE);
    /* Libera la memoria */
    g_free(buffer);
    /* Chiudi e via ! */
    fclose(ff);

and with some files it LODA only the first N byes without error in 
g_locale_to_utf8 !!! 

Why ?

-- 
O-Zone !
www.zerozone.it