Re: Behaviour of getters wrt dup/ref

[David Nečas (Yeti) <yeti physics muni cz>]

On Sat, Sep 15, 2007 at 11:08:38PM -0400, Behdad Esfahbod wrote:
> On Fri, 2007-09-14 at 10:35 -0400, Alexander Larsson wrote:
> > 
> > char *      g_data_input_stream_get_line (GDataInputStream *data_stream,
> >                                           gsize             *length,
> >                                           GCancellable     *cancellable,
> >                                           GError           **error);
> > 
> > This actually reads new data from the stream, so it has to dup. One
> > could imagine a similar call that returns some form of object instead
> > of a string. 
> 
> I think it's pretty common in glib and pango at least to return
> g_strdup'ed strings.  The no-ref-count rule is mostly for objects that
> have a literal ref/unref pair.
> 
> Other than that, for functions that return read data from the stream,
> some people may have reasons to want to avoid malloc/free'ing on each
> line.  One way to work around that is to have the function take a
> GString, so you can reuse the buffer from the previous line.  I know
> most people are not a big fan of that idea though.

The right interface for this type of functions have been
already invented: that of glibc's getline.  It can allocate
new buffers, it can reuse existing buffers resizing them if
necessary -- and it can be even used with GStrings [if they
use the same memory allocator] although that's a bit dirty.

Yeti

--
http://gwyddion.net/