#define SILC_LOG_DEBUG(...)

    This is a special wrapper to the debugging output (usually stderr).
    The standard behaviour is the same as SILC_LOG_INFO, with the difference
    that this macro also depends on the global define SILC_DEBUG.

    Undefining SILC_DEBUG causes these functions to be defined to an empty
    value, thus removing all debug logging calls from the compiled
    application.

    #if defined(SILC_DEBUG)
    #define SILC_LOG_DEBUG(fmt) silc_log_output_debug(__FILE__,     \
                                    __FUNCTION__,                   \
                                    __LINE__,                       \
                                    silc_format fmt)
    #define SILC_NOT_IMPLEMENTED(string)                                    \
      SILC_LOG_INFO(("*********** %s: NOT IMPLEMENTED YET", string));
    #else
    #define SILC_LOG_DEBUG(fmt) do { } while(0)
    #define SILC_NOT_IMPLEMENTED(string) do { } while(0)
    #endif  /* SILC_DEBUG */