Re: gtk_tree_model_get ()

[Tim Müller <zen18864 zen co uk>]

On Tuesday 11 January 2005 08:58, Hubert Sokolowski wrote:

> so as I understand that I have to free place_string_here, for example
>
> gchar *s;
> gtk_tree_model_get (model, &iter,
>                         COLUMN_BLOCKED, &s,
>                         -1);
>     if (s[0] == 'T')
>       s = "Odblokuj";
>     else
>       s = "Zablokuj";
>     g_free (s);
>
> but I get segmentation fault on g_free (s), and valgrind says
> Invalid free()
> Address 0x8068C2A is not stack'd, malloc'd or (recently) free'd
>
> I want to know if I misunderstood the docs or the docs lies.

You are assigning a constant string to  s  and then free that - no wonder it 
segfaults on you. This will work:

 gchar *s;
 gtk_tree_model_get (model, &iter,
                         COLUMN_BLOCKED, &s,
                         -1);
 g_print ("s = '%s'\n", s);
 g_free (s);


This will segfault:

 gchar *s;
 s = "foobar";
 g_free (s);

On a side note, s will be set to NULL by gtk_tree_model_get() if you haven't 
put a string into the model yet, so s[0] will segfault as well in case you're 
ever accessing an empty row/column).

Cheers
 -Tim