Re: Memory question

[Roger Leigh <rleigh whinlatter ukfsn org>]

David Rosal <david rosal upf edu> writes:

> Allin Cottrell wrote:
>
> > gchar *text = g_strdup_printf("banana %d", i);
> > gtk_entry_set_text(GTK_ENTRY(entry), text);
> > g_free(text);
>
> Is the above code really safe?
>
> You're passing the address of "text" to the function 
> gtk_entry_set_text(). Next you g_free() that address, so AFAIK the 
> memory manager marks it as free.
> Isn't it dangerous? I mean, after g_free() any call that requests for 
> memory (g_strdup, g_malloc, ...) can overwrite that memory chunk, 
> changing the text in the GtkEntry. Am I right?

No.  gtk_entry_set_text() will keep its own copy of the text
internally, which is contained within the GtkEntry object.  Once you
set the text, you can safely free your copy.  If it didn't work this
way, you would quickly run into all sorts of memory leaks.


Regards,
Roger

-- 
Roger Leigh
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