compiling gtk program

[Viveka Nathan K <vivek lantana tenet res in>]

Hi..
  I took the sample program given in GTK documentation (helloworld.c) and I compiled it.
 It gives the error as

:
:
/usr/include/gtk-1.2/glib/gtypes.h:41: syntax error before "typedef"
:
:
/usr/include/gtk-1.2/glib/garray.h:32: parse error before "G_BEGIN_DECLS"
/usr/include/gtk-1.2/glib/garray.h:34: syntax error before "typedef"
:
:

what is that 'G_BEGIN_DECLS'

I went through that gtypes.h.. there it is like as follows.  What should I do to compile the program ?

:
:
#include <glibconfig.h>

G_BEGIN_DECLS

/* Provide type definitions for commonly used types.
typedef char   gchar;
typedef short  gshort;
:
:

-- 


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Viveka Nathan K, DON Lab, IITM, Chennai-36, India. Ph:044-22578904/8353        
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All condemnation of others really condemns ourselves - Swami Vivekananda