1 <!doctype linuxdoc system>
5 <!-- Title information -->
9 <!-- NOTE: Use only one author tag, otherwise sgml2txt barfs - TRG -->
10 <author>Nathan Froyd, Tony Gale, Shawn T. Amundson.
13 This document is intended to answer questions that are likely to be
14 frequently asked by programmers using GTK+ or people who are just
15 looking at using GTK+.
18 <!-- Table of contents -->
21 <!-- Begin the document -->
23 <!-- ***************************************************************** -->
24 <sect>General Information
26 <!-- ----------------------------------------------------------------- -->
29 The authors of GTK+ are:
32 <item>Peter Mattis (petm@xcf.berkeley.edu)
33 <item>Spencer Kimball (spencer@xcf.berkeley.edu)
34 <item>Josh MacDonald (jmacd@xcf.berkeley.edu)
36 GTK+ is distributed under the GNU Library General Public License
38 <!-- ----------------------------------------------------------------- -->
41 GTK+ is a small and efficient widget set designed with the general look
42 and feel of Motif. In reality, it looks much better than Motif. It
43 contains common widgets and some more complex widgets such as a file
44 selection, and color selection widgets.
46 GTK+ provides some unique features. (At least, I know of no other widget
47 library which provides them). For
48 example, a button does not contain a label, it contains a child widget,
49 which in most instances will be a label.
50 However, the child widget can also be a pixmap, image or any combination
51 possible the programmer desires.
52 This flexibility is adhered to throughout the library.
54 <!-- ----------------------------------------------------------------- -->
55 <sect1>What is the + in GTK+?
57 Peter Mattis informed the gtk mailing list that:
59 "I originally wrote gtk which included the three libraries, libglib,
60 libgdk and libgtk. It featured a flat widget hierarchy. That is, you
61 couldn't derive a new widget from an existing one. And it contained
62 a more standard callback mechanism instead of the signal mechanism now
63 present in gtk+. The + was added to distinguish between the original
64 version of gtk and the new version. You can think of it as being an
65 enhancement to the original gtk that adds object oriented features."
68 <!-- ----------------------------------------------------------------- -->
69 <sect1>Does the G in GTK+ stand for General, Gimp, or GNU?
71 Peter Mattis informed the gtk mailing list that:
73 "I think the last time Spencer and I talked about it we decided on
74 GTK = Gimp ToolKit. But I don't know for sure. Its definately not
78 <!-- ----------------------------------------------------------------- -->
79 <sect1>Where is the documentation for GTK+?
81 In the GTK+ distribution's doc/ directory you will find the
82 reference material for both GTK and GDK, this FAQ and the
85 In addition, you can find links to HTML versions of these documents
87 <htmlurl url="http://www.gimp.org/gtk/"
88 name="http://www.gimp.org/gtk/">.
90 The Tutorial and FAQ can also be found at
91 <htmlurl url="http://www.geocities.com/ResearchTriangle/Lab/4299/"
92 name="http://www.geocities.com/ResearchTriangle/Lab/4299/">.
94 <!-- ----------------------------------------------------------------- -->
95 <sect1>Is there a mailing list (or mailing list archive) for GTK+?
97 There are two mailing lists:
99 <item>A mailing list for discussion of development of GTK based applications
100 is hosted at gtk-app-devel-list@redhat.com. To subscribe send an
101 email message to <htmlurl url="mailto:gtk-app-devel-list-request@redhat.com"
102 name="gtk-app-devel-list-request@redhat.com">
103 with <em>subscribe</em> in the <bf>subject</bf>.
105 <item>A mailing list for discussion of development of GTK is hosted
106 at gtk-list@redhat.com. To subscribe send an
107 email message to <htmlurl url="mailto:gtk-list-request@redhat.com"
108 name="gtk-list-request@redhat.com">
109 with <em>subscribe</em> in the <bf>subject</bf>.
111 A searchable archive of the mailing list can be found at <htmlurl url="http://archive.redhat.com/gtk-list" name="http://archive.redhat.com/gtk-list">
113 <!-- ----------------------------------------------------------------- -->
114 <sect1>The gtk-list hasn't had any traffic for days, is it dead?
116 No, everyone's just busy coding.
118 <!-- ----------------------------------------------------------------- -->
119 <sect1>How to get help with GTK+
121 First, make sure your question isn't answered in the documentation, this
122 FAQ or the tutorial. Done that? You're sure you've done that, right? In
123 that case, the best place to post questions is to the GTK+ mailing list.
125 <!-- ----------------------------------------------------------------- -->
126 <sect1>How to report bugs in GTK+
128 Bug reports should be sent to the GTK+ mailing list.
130 <!-- ----------------------------------------------------------------- -->
131 <sect1>What applications have been written with GTK+?
133 Some applications which use GTK+ are:
135 <item>GIMP (<htmlurl url="http://www.XCF.Berkeley.EDU/~gimp/"
136 name="http://www.XCF.Berkeley.EDU/~gimp/"> ),
137 an image manipulation program
138 <item>Gsumi (<htmlurl url="http://www.msc.cornell.edu/~otaylor/gsumi/gsumi.html"
139 name="http://www.msc.cornell.edu/~otaylor/gsumi/gsumi.html">),
140 a fun B+W doodling program with XInput support.
141 <item>GUBI (<htmlurl url="http://www.SoftHome.net/pub/users/timj/gubi/index.htm"
142 name="http://www.SoftHome.net/pub/users/timj/gubi/index.htm">),
143 a user interface builder
144 <item>Gzilla (<htmlurl url="http://www.levien.com/gzilla/" name="http://www.levien.com/gzilla/">),
146 <item>SANE (<htmlurl url="http://www.azstarnet.com/~axplinux/sane/" name="http://www.azstarnet.com/~axplinux/sane/"> ),
147 a universal scanner interface
148 <item>XQF (<htmlurl url="http://www.botik.ru/~roma/quake/" name="http://www.botik.ru/~roma/quake/">),
149 a QuakeWorld/Quake2 server browser and launcher
150 <item>ElectricEyes (<htmlurl url="http://www.labs.redhat.com/ee.shtml" name="http://www.labs.redhat.com/ee.shtml">),
151 an image viewer that aims to be a free replacement for xv
152 <item>GPK - the General Proxy Kit (<htmlurl url="http://www.humanfactor.com/gpk/" name="http://www.humanfactor.com/gpk/">),
153 an add-on library to permit thread-safe access to GTK+
154 <item>GCK - the General Convenience Kit (<htmlurl url="http://www.ii.uib.no/~tomb/gck.html" name="http://www.ii.uib.no/~tomb/gck.html">),
155 miscellaneous functions intended to ease color handling, UI construction,
156 vector operations, and math functions
157 <item>GDK Imlib (<htmlurl url="http://www.labs.redhat.com/imlib/" name="http://www.labs.redhat.com/imlib/">),
158 a fast image loading and manipulation library for GDK
161 In addition to the above, the GNOME project (<htmlurl url="http://www.gnome.org"
162 name="http://www.gnome.org">)
163 is using GTK+ to build a free desktop for Linux. Many more programs can be found
166 <!-- ***************************************************************** -->
167 <sect>How to find, configure, install, and troubleshoot GTK+
169 <!-- ***************************************************************** -->
171 <!-- ----------------------------------------------------------------- -->
172 <sect1>What do I need to run GTK+?
174 To compile GTK+, all you need is a C compiler (gcc) and the X Window System
175 and associated libraries on your system.
177 <!-- ----------------------------------------------------------------- -->
178 <sect1>Where can I get GTK+?
180 The canonical site is:
182 ftp://ftp.gimp.org/pub/gtk
184 Of course, any mirrors of ftp.gimp.org should have the latest version, too.
186 <sect1>How do I configure/compile GTK+?
188 Generally, all you will need to do is issue the commands:
193 in the gtk+-version/ directory.
195 <!-- ----------------------------------------------------------------- -->
196 <sect1>When compiling GTK+ I get an error like:
197 <tt/make: file `Makefile' line 456: Syntax error/
199 Make sure that you are using GNU make (use <tt/make -v/ to check). There are
200 many weird and wonderful versions of make out there, and not all of them
201 handle the automatically generated Makefiles.
203 <!-- ----------------------------------------------------------------- -->
205 <sect1>I've compiled and installed GTK+, but I can't get any programs to link
208 This problem is most often encountered when the GTK+ libraries can't be
209 found or are the wrong version. Generally, the compiler will complain about an
210 'unresolved symbol'. There are two things you need to check:
212 <item>Make sure that the libraries can be found. You want to edit
213 /etc/ld.so.conf to include /usr/local/lib (or whereever you installed GTK+),
214 so it looks something like:
219 Then you need to run /sbin/ldconfig as root.
221 <item>Make sure the linker is finding the correct set of libraries. If you
222 have a Linux distribution that installs GTK+ (e.g. RedHat 5.0) then this
223 older version may be used. Now (assuming you have a RedHat
224 system), issue the command
228 You may also want to remove the packages that depend on gtk (rpm will tell you
229 which ones they are). If you don't have a RedHat Linux system, check to make sure
230 that neither <verb>/usr/lib</verb> or <verb>/usr/local/lib</verb> contain any of
231 the libraries libgtk, libgdk, libglib, or libgck. If they do exist, remove them
232 (and any gtk include files, such as /usr/include/gtk and /usr/include/gdk)
236 <!-- ***************************************************************** -->
237 <sect>Development of GTK+
238 <!-- ***************************************************************** -->
240 <!-- ----------------------------------------------------------------- -->
241 <sect1>Whats this CVS thing that everyone keeps talking about, and how do I access it?
243 CVS is the Concurent Version System and is a very popular mean of
244 version control for software projects. It is designed to allow multiple
245 authors to be able to simultanously operate on the same source tree.
246 This source tree is centrally maintained, but each developer has a
247 local mirror of this repository that they make there changes to.
249 The GTK+ developers use a CVS repository to store the master copy of
250 the current development version of GTK+. As such, people wishing to
251 contribute patches to GTK+ should generate them against the CVS version.
252 Normal people should use the packaged releases.
254 The CVS toolset is available as RPM packages from the usual RedHat sites.
255 The latest version is available at
256 <htmlurl url="http://download.cyclic.com/pub/"
257 name="<http://download.cyclic.com/pub/>">
259 Anyone can download the latest CVS version of GTK+ by using anonymous access
260 using the following steps:
262 <item> In a bourne shell descendant (e.g. bash) type:
264 export CVSROOT=':pserver:anonymous@cvs.gimp.org:/debian/home/gnomecvs'
266 <item>Next, the first time the source tree is checked out, a cvs login
271 This will ask you for a password. There is no password for cvs.gimp.org,
272 so just enter a carriage return.
273 <item>To get the tree and place it in a subdir of your current working directory, issue the command:
278 <!-- ----------------------------------------------------------------- -->
279 <sect1>How can I contribute to GTK+?
281 It's simple. If something doesn't work like you think it should in a program,
282 check the documentation to make sure you're not missing something. If it is a
283 true bug or missing feature, track it down in the GTK+ source, change it,
284 and then generate a patch in the form of a 'context diff'. This can be done
285 using a command such as <tt/diff -ru <oldfile> <newfile>/.
286 Then upload the patchfile to:
288 ftp://ftp.gimp.org/incoming
290 along with a README file. Make sure you follow the naming conventions or your
291 patch will just be deleted! The filenames should be of this form:
293 gtk-<username>-<date yymmdd-n>.patch.gz
294 gtk-<username>-<date yymmdd-n>.patch.README
296 The "n" in the date indicates a unique number (starting from 0)
297 of patches you uploaded that day. It should be 0, unless you
298 upload more than one patch in the same day.
302 gtk-gale-982701-0.patch.gz
303 gtk-gale-982701-0.patch.README
305 Once you upload <em>anything</em>, send the README to ftp-admin@gimp.org
307 <!-- ----------------------------------------------------------------- -->
308 <sect1>How do I know if my patch got applied, and if not, why not?
310 Uploaded patches will be moved to <tt>ftp://ftp.gimp.org/pub/gtk/patches</tt>
311 where one of the GTK+ development team will pick them up. If applied, they
312 will be moved to <tt>/pub/gtk/patches/old</tt>.
314 Patches that aren't applied, for whatever reason, are moved to
315 <tt>/pub/gtk/patches/unapplied</tt> or <tt>/pub/gtk/patches/outdated</tt>.
316 At this point you can ask on the <tt/gtk-list/ mailing list why your patch
317 wasn't applied. There are many possible reasons why patches may not be
318 applied, ranging from it doesn't apply cleanly, to it isn't right. Don't
319 be put off if your patch didn't make it first time round.
321 <!-- ----------------------------------------------------------------- -->
322 <sect1>What is the policy on incorporating new widgets into the library?
324 This is up to the authors, so you will have to ask them once you
325 are done with your widget. As a general guideline, widgets that are
326 generally useful, work, and are not a disgrace to the widget set will
329 <!-- ----------------------------------------------------------------- -->
330 <sect1>Is anyone working on bindings for languages other than C?
334 <item>a C++ wrapper for GTK+ called gtk--. You can find the home page at:
336 http://www.cs.tut.fi/~p150650/gtk/gtk--.html
340 ftp://ftp.gimp.org/pub/gtk/gtk--/
344 <item>There are two Objective-c bindings currently in development:
348 <item>The <htmlurl url="http://www.gnome.org/" name="GNOME project's"> package
349 of choice is obgtk. Objgtk is based on the Object class and is maintained by
350 <htmlurl url="mailto:sopwith@cuc.edu" name="Elliot Lee">. Apparently, objgtk
351 is being accepted as the `standard' Objective-C binding for GTK+.
353 <item>If you are more inclined towards the
354 <htmlurl url="http://www.gnustep.org/" name="GNUstep project">,
355 you may want to check out GTKKit by
356 <htmlurl url="mailto:helge@mdlink.de" name="Helge Heszlig">.
357 The intention is to setup a GTK+ binding using the FoundationKit.
358 GTKKit includes nicities like writing a XML-type template file to
359 construct a GTK+ interface.
365 ftp://ftp.gimp.org/pub/gtk/perl
368 <item>Guile bindings. The home page is at:
370 http://www.ping.de/sites/zagadka/guile-gtk/
372 By the way, Guile is the GNU Project's implemention of R4RS Scheme (the
373 standard). If you like Scheme, you may want to take a look at this.
376 <item>David Monniaux reports:
377 <quote>I've started a gtk-O'Caml binding system.
378 The basics of the system, including callbacks, work fine.
380 The current development is in
381 http://www.ens-lyon.fr/~dmonniau/arcs/
385 Several python-gtk interfaces have been done. python-gtk is at:
387 http://www.acs.ucalgary.cs/~nashceme/python-gtk/
389 If you try python-gtk and don't like it, there's also pygtk located at:
391 ftp://ftp.gimp.org/pub/gtk/python/
395 There's a OpenGL/Mesa widget available for GTK+. Grab it at:
397 http://www.sakuranet.or.jp/~aozasa/shige/doc/comp/gtk/gtkGL/files-en.html
402 <!-- ***************************************************************** -->
403 <sect>Development with GTK+
404 <!-- ***************************************************************** -->
405 <!-- ----------------------------------------------------------------- -->
406 <sect1>How do I get started?
408 So, after you have installed GTK+ there are a couple of things that can
409 ease you into developing applications with it. There is the
410 GTK+ Tutorial <htmlurl url="http://www.gimp.org/gtk/tutorial/"
411 name="<http://www.gimp.org/gtk/tutorial/>">, which is undergoing
412 development. This will introduce you to writing applications using C.
414 The Tutorial doesn't (yet) contain information on all of the widgets
415 that are in GTK+. For example code on how to use the basics of all the
416 GTK+ widgets you should look at the file gtk/testgtk.c (and associated
417 source files) within the GTK+ distribution. Looking at these exmaples will
418 give you a good grounding on what the widgets can do.
420 <sect1>What widgets are in GTK?
422 The GTK+ Tutorial lists the following widgets:
434 | | | `GtkAspectFrame
439 | | | | `GtkCheckMenuItem
440 | | | | `GtkRadioMenuItem
444 | | +GtkColorSelectionDialog
446 | | | `GtkInputDialog
447 | | `GtkFileSelection
456 | | +GtkColorSelection
506 <!-- ----------------------------------------------------------------- -->
507 <sect1>How can I prevent redrawing and resizing while I change multiple widgets?
509 Use gtk_container_disable_resize and gtk_container_enable_resize around the
510 code where you are changing a lot of stuff. This will result in much faster
511 speed since it will prevent resizing of the entire widget hierarchy.
513 <!-- ----------------------------------------------------------------- -->
514 <sect1>How do I catch a double click event in a list widget?
516 Tim Janik wrote to gtk-list (slightly modified):
518 Define a signal handler:
522 signal_handler_event(GtkWiget *widget, GdkEvenButton *event, gpointer func_data)
524 if (GTK_IS_LIST_ITEM(widget) &&
525 (event->type==GDK_2BUTTON_PRESS ||
526 event->type==GDK_3BUTTON_PRESS) ) {
527 printf("I feel %s clicked on button %d\",
528 event->type==GDK_2BUTTON_PRESS ? "double" : "triple",
536 And connect the handler to your object:
540 /* list, list item init stuff */
542 gtk_signal_connect(GTK_OBJECT(list_item),
543 "button_press_event",
544 GTK_SIGNAL_FUNC(signal_handler_event),
549 gtk_signal_connect(GTK_OBJECT(list_item),
550 "button_release_event",
551 GTK_SIGNAL_FUNC(signal_handler_event),
558 <!-- ----------------------------------------------------------------- -->
559 <sect1>How do I find out about the selection of a GtkList?
562 Get the selection something like this:
565 sel = GTK_LIST(list)->selection;
568 This is how GList is defined (quoting glist.h):
570 typedef struct _GList GList;
580 A GList structure is just a simple structure for doubly linked lists.
581 there exist several g_list_*() functions to modify a linked list in
582 glib.h. However the GTK_LIST(MyGtkList)->selection is maintained
583 by the gtk_list_*() functions and should not be modified.
585 The selection_mode of the GtkList determines the selection
586 facilities of a GtkList and therefore the contents
587 of GTK_LIST(AnyGtkList)->selection:
590 selection_mode GTK_LIST()->selection contents
591 ------------------------------------------------------
593 GTK_SELECTION_SINGLE) selection is either NULL
594 or contains a GList* pointer
595 for a single selected item.
597 GTK_SELECTION_BROWSE) selection is NULL if the list
598 contains no widgets, otherwise
599 it contains a GList* pointer
600 for one GList structure.
601 GTK_SELECTION_MULTIPLE) selection is NULL if no listitems
602 are selected or a a GList* pointer
603 for the first selected item. that
604 in turn points to a GList structure
605 for the second selected item and so
608 GTK_SELECTION_EXTENDED) selection is NULL.
611 The data field of the GList structure GTK_LIST(MyGtkList)->selection points
612 to the first GtkListItem that is selected. So if you would like to determine
613 which listitems are selected you should go like this:
618 gchar *list_items[]={
624 guint nlist_items=sizeof(list_items)/sizeof(list_items[0]);
625 GtkWidget *list_item;
629 gtk_list_set_selection_mode(GTK_LIST(list), GTK_SELECTION_MULTIPLE);
630 gtk_container_add(GTK_CONTAINER(AnyGtkContainer), list);
631 gtk_widget_show (list);
633 for (i = 0; i < nlist_items; i++)
635 list_item=gtk_list_item_new_with_label(list_items[i]);
636 gtk_object_set_user_data(GTK_OBJECT(list_item), (gpointer)i);
637 gtk_container_add(GTK_CONTAINER(list), list_item);
638 gtk_widget_show(list_item);
643 To get known about the selection:
648 items=GTK_LIST(list)->selection;
650 printf("Selected Items: ");
652 if (GTK_IS_LIST_ITEM(items->data))
653 printf("%d ", (guint)
654 gtk_object_get_user_data(items->data));
660 <!-- ----------------------------------------------------------------- -->
661 <sect1>Is it possible to get some text displayed which is truncated to fit inside its allocation?
663 GTK's behavior (no clipping) is a consequence of its attempts to
664 conserve X resources. Label widgets (among others) don't get their own
665 X window - they just draw their contents on their parent's window.
666 While it might be possible to have clipping occur by setting the clip
667 mask before drawing the text, this would probably cause a substantial
670 Its possible that, in the long term, the best solution to such
671 problems might be just to change gtk to give labels X windows.
672 A short term workaround is to put the label widget inside another
673 widget that does get it's own window - one possible candidate would
674 be the viewport widget.
677 viewport = gtk_viewport (NULL, NULL);
678 gtk_widget_set_usize (viewport, 50, 25);
679 gtk_viewport_set_shadow_type (GTK_VIEWPORT(viewport), GTK_SHADOW_NONE);
680 gtk_widget_show(viewport);
682 label = gtk_label ("a really long label that won't fit");
683 gtk_container_add (GTK_CONTAINER(viewport), label);
684 gtk_widget_show (label);
687 If you were doing this for a bunch of widgets, you might want to
688 copy gtkviewport.c and strip out the adjustment and shadow
689 functionality (perhaps you could call it GtkClipper).
691 <!-- ----------------------------------------------------------------- -->
692 <sect1>Why don't the contents of a button move when the button is pressed? Here's a patch to make it work that way...
696 The reason buttons don't move their child down and to the right when
697 they are depressed is because I don't think that's what is happening
698 visually. My view of buttons is that you are looking at them straight
699 on. That is, the user interface lies in a plane and you're above it
700 looking straight at it. When a button gets pressed it moves directly
701 away from you. To be absolutely correct I guess the child should
702 actually shrink a tiny amount. But I don't see why the child should
703 shift down and to the left. Remember, the child is supposed to be
704 attached to the buttons surface. Its not good for it to appear like
705 the child is slipping on the surface of the button.
707 On a more practical note, I did implement this at one point and
708 determined it didn't look good and removed it.
710 <!-- ----------------------------------------------------------------- -->
711 <sect1>How can I define a separation line in a menu?
713 See the <htmlurl url="http://www.gimp.org/gtk/tutorial/"
714 name="Tutorial"> for information on how to create menus.
715 However, to create a separation line in a menu, just insert an
719 menuitem = gtk_menu_item_new();
720 gtk_menu_append(GTK_MENU(menu), menuitem);
721 gtk_widget_show(menuitem);
724 <!-- ----------------------------------------------------------------- -->
725 <sect1>How can I right justify a menu, such as Help, when using the MenuFactory?
727 Use something like the following:
730 menu_path = gtk_menu_factory_find (factory, "<MyApp>/Help");
731 gtk_menu_item_right_justify(menu_path->widget);
734 <!-- ***************************************************************** -->
736 <!-- ***************************************************************** -->
738 <!-- ----------------------------------------------------------------- -->
741 gdk is basically a wrapper around the standard Xlib function calls. If you are
742 at all familiar with Xlib, a lot of the functions in gdk will require little
743 or no getting used to. All functions are written to provide an easy way
744 to access Xlib functions in an easier an slightly more intuitive manner.
745 In addition, since gdk uses glib (see below), it will be more portable
746 and safer to use on multiple platforms.
748 <!-- Examples, anybody? I've been mulling some over. NF -->
750 <sect1>How do I use color allocation?
752 One of the nice things about GDK is that it's based on top of Xlib; this is
753 also a problem, especially in the area of color management. If you want
754 to use color in your program (drawing a rectangle or such, your code
755 should look something like this:
766 /* first, create a GC to draw on */
767 gc = gdk_gc_new(widget->window);
769 /* find proper dimensions for rectangle */
770 gdk_window_get_size(widget->window, &width, &height);
772 /* the color we want to use */
773 color = (GdkColor *)malloc(sizeof(GdkColor));
775 /* red, green, and blue are passed values, indicating the RGB triple
776 * of the color we want to draw. Note that the values of the RGB components
777 * within the GdkColor are taken from 0 to 65535, not 0 to 255.
779 color->red = red * (65535/255);
780 color->green = green * (65535/255);
781 color->blue = blue * (65535/255);
783 /* the pixel value indicates the index in the colormap of the color.
784 * it is simply a combination of the RGB values we set earlier
786 color->pixel = (gulong)(red*65536 + green*256 + blue);
788 /* However, the pixel valule is only truly valid on 24-bit (TrueColor)
789 * displays. Therefore, this call is required so that GDK and X can
790 * give us the closest color available in the colormap
792 gdk_color_alloc(gtk_widget_get_colormap(widget), color);
794 /* set the foreground to our color */
795 gdk_gc_set_foreground(gc, color);
797 /* draw the rectangle */
798 gdk_draw_rectangle(widget->window, gc, 1, 0, 0, width, height);
805 <!-- ***************************************************************** -->
807 <!-- ***************************************************************** -->
809 <!-- ----------------------------------------------------------------- -->
812 glib is a library of useful functions and definitions available for use
813 when creating GDK and GTK applications. It provides replacements for some
814 standard libc functions, such as malloc, which are buggy on some systems.
816 It also provides routines for handling:
818 <item>Doubly Linked Lists
819 <item>Singly Linked Lists
821 <item>String Handling
822 <item>A Lexical Scanner
823 <item>Error Functions
826 <!-- Some Examples might be useful here! NF -->
828 <!-- ----------------------------------------------------------------- -->
829 <sect1>Why use g_print, g_malloc, g_strdup and fellow glib functions ?
831 Thanks to Tim Janik who wrote to gtk-list: (slightly modified)
833 Regarding g_malloc(), g_free() and siblings, these functions are much safer
834 than thier libc equivalences. For example, g_free() just returns if called
835 with NULL. Also, if USE_DMALLOC is defined, the definition for these
836 functions changes (in glib.h) to use MALLOC(), FREE() etc... If MEM_PROFILE
837 or MEM_CHECK are defined, there are even small statistics made counting
838 the used block sizes (shown by g_mem_profile() / g_mem_check()).
840 Considering the fact that glib provides an interface for memory chunks
841 to save space if you have lots of blocks that are always the same size
842 and to mark them ALLOC_ONLY if needed, it is just straight forward to
843 create a small saver (debug able) wrapper around the normal malloc/free
844 stuff as well - just like gdk covers Xlib. ;)
846 Using g_error() and g_warning() inside of applications like the GIMP
847 that fully rely on gtk even gives the opportunity to pop up a window
848 showing the messages inside of a gtk window with your own handler
849 (by using g_set_error_handler()) along the lines of gtk_print()
850 (inside of gtkmain.c).
853 <!-- ***************************************************************** -->
854 <sect>GTK+ FAQ Contributions, Maintainers and Copyright
856 If you would like to make a contribution to the FAQ, send either one of us
857 an e-mail message with the exact text you think should be included (question and
858 answer). With your help, this document can grow and become more useful!
860 This document is maintained by Nathan Froyd
861 <htmlurl url="mailto:maestrox@geocities.com" name="<maestrox@geocities.com>">
862 and Tony Gale <htmlurl url="mailto:gale@gimp.org" name="<gale@gimp.org>">.
863 This FAQ was created by Shawn T. Amundson <htmlurl url="mailto:amundson@gimp.org"
864 name="<amundson@gimp.org>">who continues to provide support.
866 The GTK+ FAQ is Copyright (C) 1997,1998 by Shawn T. Amundson, Nathan Froyd and Tony Gale.
868 Permission is granted to make and distribute verbatim copies of this manual provided the
869 copyright notice and this permission notice are preserved on all copies.
871 Permission is granted to copy and distribute modified versions of this document under the conditions
872 for verbatim copying, provided that this copyright notice is included exactly as in the original,
873 and that the entire resulting derived work is distributed under the terms of a permission
874 notice identical to this one.
876 Permission is granted to copy and distribute translations of this document into another language,
877 under the above conditions for modified versions.
879 If you are intending to incorporate this document into a published work, please contact one of
880 the maintainers, and we will make an effort to ensure that you have the most up to date
881 information available.
883 There is no guarentee that this document lives up to its intended
884 purpose. This is simply provided as a free resource. As such,
885 the authors and maintainers of the information provided within can
886 not make any guarentee that the information is even accurate.