Re: problem in gtk programming

[walt <wa1ter@xxxxxxxxxxxxx>]

dark0s Optik wrote:
> I am triyng to programming with gtk over DragonFly.
> My sample code is the follows:
>
> #include<gtk/gtk.h>
> ...
>
> The gcc output is:
>
> #gcc prova.c -o prova
> ...

Hi Savio,

The gtk header files are in /usr/pkg/include because you are
using the gtk package from pkgsrc (like most of us).  That's
fine if you are building another pkgsrc package because all
pkgsrc packages are smart enough to look in /usr/pkg/include
for the required header files.

But, if you are writing your own code you need to tell gcc
where to look for the gtk headers, because gcc is only smart
enough to look in /usr/include -- it knows nothing about the
/usr/pkg/include directory unless you tell it.

So you need to do something like this:
#gcc -I/usr/pkg -I/usr/pkg/include prova.c -o prova

But wait, now the loader doesn't know where to look for the
gtk libraries, so you will get a different error about that.

The gnu autotools people devised the pkg-config system to
solve this very common problem.  Try this:
#pkg-config --list-all | grep gtk (look for gtk+-2.0)

#pkg-config --cflags --libs gtk+-2.0
-I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include -I/usr/include/atk-1.0 
-I/usr/include/cairo -I/usr/include/pango-1.0 -I/usr/include/glib-2.0 
-I/usr/lib/glib-2.0/include -I/usr/include/freetype2 
-I/usr/include/libpng12 -I/usr/include/pixman-1  -lgtk-x11-2.0 
-lgdk-x11-2.0 -latk-1.0 -lgdk_pixbuf-2.0 -lpangocairo-1.0 -lpango-1.0 
-lcairo -lgobject-2.0 -lgmodule-2.0 -ldl -lglib-2.0

That horrible list of flags is what you need to give gcc to compile
*and* link your program against gtk -- but I'm doing this on a linux
machine and you should see different flags on your dragonfly machine.

I leave the rest as an exercise for the reader ;o)