[lwip-devel] Understading LWIP_DEBUG()

[Gisle Vanem]

I'm utterly bewildered by all the macros in lwIP. E.g. the
LWIP_DEBUGF() macro is defined as:

#define LWIP_DEBUGF(debug, message) do { \
                              if ( \
                                  ((debug) & LWIP_DBG_ON) && \
                                  ((debug) & LWIP_DBG_TYPES_ON) && \
                                   ((s16_t)((debug) & LWIP_DBG_MASK_LEVEL) >= 
LWIP_DBG_MIN_LEVEL) ) { \
                                LWIP_PLATFORM_DIAG(message); \
                  ...

And used as e.g:    
 LWIP_DEBUGF( PING_DEBUG, ("ping: send "));

I got an idea from contrib/ports/unix/proj/minimal/main.c (debug_flags),
but failed to see how I can mask PING_DEBUG==1 in my lwipopts.h to get
the message printed.

In my lwipopts.h I have:
 extern unsigned int debug_flags;
 #define LWIP_DBG_TYPES_ON debug_flags

an in src/contrib/ports/win32/test.c (main.c) I have:
 const char *e = getenv("LWIP_DEBUG");
 if (e)
   sscanf(e,"0x%x", &debug_flags);

What should I set $LWIP_DEBUG to to get some output? Tried
'0x80', but nothing...

--gv