From: WHS <wouters@cistron.nl>
  To  : ggi-develop@eskimo.com
  Date: Fri, 04 Sep 1998 02:28:18 +0200

Re: Improved debugging system for libggi

Marcus Sundberg wrote:

> I've enhanced the debugging system in libggi a bit:
> 
> We now have the following types for debug messages.
> 
> #define GGIDEBUG_CORE           (1<<1)  /*   2 */
> #define GGIDEBUG_MODE           (1<<2)  /*   4 */
> #define GGIDEBUG_COLOR          (1<<3)  /*   8 */
> #define GGIDEBUG_DRAW           (1<<4)  /*  16 */
> #define GGIDEBUG_MISC           (1<<5)  /*  32 */
> #define GGIDEBUG_LIBS           (1<<6)  /*  64 */
> #define GGIDEBUG_EVENTS         (1<<7)  /* 128 */
> 
> which may be ored together as desired in the GGI_DEBUG environment
> variable.

Isn't it much nicer to use debug prefixes (inxfixes, postfixes) like I
use in gsi, e.g. use GGI_DEBUG_CORE = n to give level n output of the
core section, GGI_DEBUG_EVENTS=0 switches off event  messages. It's
going to be a nightmare trying to remember which bit was assigned to
what part of libggi.
The way I use this in gsi is:

#define DEBUG_PREFIX "L_"
#include <gsi/gsi_debug.h>

Also, GGI_DEBUG could be used to override this, i.e. if GGI_DEBUG=1 then
all output with level >=1 is shown. Might mean some changes to the ggi
debug files but isn't difficult to do.

Wouter