Macro to turn off printf statements

Question

What MACRO can be used to switch off printf statements, rather than removing them all for deployment builds, I just want to switch them off, skip them, ignore them.

Answer 1

#ifdef IGNORE_PRINTF
#define printf(fmt, ...) (0)
#endif

See also C #define macro for debug printing which discusses some important issues closely related to this.

Answer 2

If you want to avoid the potential warning that Jonathan's answer may give you and if you don't mind an empty call to printf you could also do something like

#define printf(...) printf("")

This works because C macros are not recursive. The expanded printf("") will just be left as such.

Another variant (since you are using gcc) would be something like

inline int ignore_printf(char const*, ...) 
         __attribute__ ((format (printf, 1, 2)));
inline int ignore_printf(char const*, ...) { return 0; }

#define printf ignore_printf

and in one compilation unit

int ignore_printf(char const*, ...)

Answer 3

Use this macro to enable or disable the printf.

//Uncomment the following line to enable the printf function.
//#define ENABLE_PRINTF
#ifdef ENABLE_PRINTF
    #define    DEBUG_PRINTF(f,...)    printf(f,##__VA_ARGS__)
#else
    #define    DEBUG_PRINTF(f,...)
#endif

Then call "DEBUG_PRINTF" instead of "printf".

For example:

DEBUG_PRINTF("Hello world: %d", whateverCount);

Answer 4

Below simple function serves the purpose, I use the same.

int printf(const char *fmt, ...)
{
return (0)
}