Okay... I puzzled over the assertion macro posted above, and the replacement text of ";" for the #ifndef side doesn't seem to work under Lite-C pure mode. I've written some logging related macros that use a work around for the #ifndef side:

EDITTED: I think it best to add a reminder that logging is on, so I added some addtional code to show that logging is on and when the log file is closed.
Code:

---

#define LOGGING

#ifdef LOGGING
	#define START_LOGGER(n)  printf("Logging is on.");FILE* LOG_HANDLE = fopen( n, "w"); if (LOG_HANDLE == NULL) error("Couldn't open log file");
	#define LOG(log_msg) fprintf( LOG_HANDLE, "%0.2d:%0.2d:%0.2d - %s\n", (int)sys_hours, (int)sys_minutes, (int)sys_seconds, (char*)#log_msg );
	#define CLOSE_LOGGER if ( LOG_HANDLE != NULL) fclose(LOG_HANDLE);printf("Log closed.");
#else
	#define COMMENT  //
	#define START_LOGGER(n)		COMMENT
	#define LOG(log_msg)		COMMENT
	#define CLOSE_LOGGER		COMMENT
#endif

...
START_LOGGER("test.log")
...
LOG( "start_panel" )
...
CLOSE_LOGGER
	

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