#define app_trace_log(...) ??

[Amit Singh]

#define app_trace_log(...) what we define here i don't understand what this function is doing ?

[monpetit]

If you compile with ENABLE_DEBUG_LOG_SUPPORT macro, app_trace_log() It's just the same printf, typically logs messages over UART. Without ENABLE_DEBUG_LOG_SUPPORT, It does nothing. All messages are end up in the trash.

app_trace.h:

#ifdef ENABLE_DEBUG_LOG_SUPPORT
  #define app_trace_log printf
#else
  #define app_trace_log(...)
#endif // ENABLE_DEBUG_LOG_SUPPORT