Hi all, after some troubles I got to setup almost all the GTK devel packages and now I'm trying to compile a program from the "Beginning Linux Programming" book (3rd edition).
The problem is that the gcc compiler doesn't recognize the:
#include <gtk/gtk.h>
saying no such file or directory.

so when I'm hardcoding it like this:
#include "/usr/include/gtk-2.0/gtk/gtk.h"

the compiler issues a lot of unresolved headers like:
$ gcc gtk1.c -o gtk1 `pkg-config -cflags -libs gtk+-2.0`
-cflags: unknown option
In file included from gtk1.c:1:
/usr/include/gtk-2.0/gtk/gtk.h:31:21: error: gdk/gdk.h: No such file or directory
/usr/include/gtk-2.0/gtk/gtk.h:32:32: error: gtk/gtkaboutdialog.h: No such file or directory
/usr/include/gtk-2.0/gtk/gtk.h:33:31: error: gtk/gtkaccelgroup.h: No such file or directory

I think there should be some environment variable telling the compiler where to look for the header files. BUT it looks like although the pkg-config program is there - it doesn't work correctly since it complains "-cflags: unknown option".

Someone please tell me how to setup the compiler or my environment to get the code to compile, here's the code of the simple app:
#include "/usr/include/gtk-2.0/gtk/gtk.h"
//<gtk/gtk.h>
int main (int argc, char *argv[])
{
GtkWidget *window;
gtk_init(&argc, &argv);
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
gtk_widget_show(window);
gtk_main ();
return 0;
}

never ever ever ever use absolute filenames in include statements, absolutely daft idea. don't.

clearly you're not using the pkgconfig command correctly, as it's complaining about the optiosn you're running it with, try --cflags instead of -cflags.

OMG!!!!
THANK YOU SO MUCH!!!! it works!!