On Wed, 2004-05-05 at 11:31 +0200, Andreas Leitner wrote:
Hi,
I am developing GTK bindings for the language Eiffel and am currently
investigating who needs to free what memory with respect to strings.
In the following scenario:
---
GtkWidget *button;
char* label_text = ...; // somehow init that text
printf ("label text: %x\n", label_text);
button = gtk_button_new_with_label (label_text);
printf ("get_text: %x\n", gtk_button_get_label (GTK_BUTTON(button)));
---
I can see that gtk_button_new_with_label actually copies the string
since the first and the second printf show two different memory
locations.
* Now am I correct when assuming that if I have dynamically allocated
the memory for 'label_text', it is my duty to free that memory again?
Yes. blah_set_X() will always copy the given property value into the object. The arguments to blah_new() merely set those properties before you get the object.
* Is this true for all the string handling in GTK? Are strings always copied, and I always need to free them? Or are there exceptions? If so is there documentation who needs to free what where and when? (;
The API docs *usually* mention when you have to free and when you don't (e.g. "you must free the returned X when no longer needed"). Further, the functions return const when you shouldn't mess with the result, and have const arguments when the object won't mess with the passed values. The only exception to this rule I'm aware of is char** arrays. http://developer.gnome.org/doc/API/2.4/gtk/gtk-question-index.html#id2505171
many thanks in advance, Andreas
--
Peace,
Jim Cape
http://ignore-your.tv
"We still name our military helicopter gunships after victims
of genocide. Nobody bats an eyelash about that: Blackhawk.
Apache. And Comanche. If the Luftwaffe named its military
helicopters Jew and Gypsy, I suppose people would notice."
-- Noam Chomsky, "Propaganda and the Public Mind"
Attachment:
signature.asc
Description: This is a digitally signed message part