gcc does not include certain .h-files

Hi there!

gcc seems not to include available files, see below:

What should I do?

Look forward to your reply/replies!
Thanks
Grahamb

In the source directory I enter:

#gcc -Wall -I/usr/include ./gtkdaq.c > ./out.log 2>&1

Response:

In file included from ./gtkdaq.c:3:
/usr/include/gtk/gtk.h:31:21: error: gdk/gdk.h: No such file or directory
In file included from /usr/include/gtk/gtkaccelgroup.h:32,
                 from /usr/include/gtk/gtkwindow.h:32,
                 from /usr/include/gtk/gtkdialog.h:32,
                 from /usr/include/gtk/gtkaboutdialog.h:28,
                 from /usr/include/gtk/gtk.h:32,
                 from ./gtkdaq.c:3:
/usr/include/gtk/gtkenums.h:30:25: error: glib-object.h: No such file or directory
etc . . . 

But, with ls -la, they are clearly available and readable:

-rw-r--r-- 1 root root 6377 Sep 30  2006 /usr/include/gtk/gtk.h
-rw-r--r-- 1 root root 11262 Sep 30  2006 /usr/include/gtk/gtkenums.h
-rw-r--r-- 1 root root 6576 Sep 30  2006 /usr/include/gtk/gtkaccelgroup.h
etc . . . 
gdk/gdk.h: 

Is the first problem. Should it have been #include <gtk/gtk.h> ?

Perhaps you did not install GDK as well as GTK?