#define macro for debug printing in C?

Question

Trying to create a macro which can be used for print debug messages when DEBUG is defined, like the following pseudo code: #define DEBUG 1 #define debug_print(args ...) if (DEBUG) fprintf(stderr, args)How is this accomplished with a macro?

Answer 1

/* should be placed in debug.h */

#include <stdio.h>

#define _DEBUG (1)

#define DEBUG_ON (1)

#define DEBUG_OFF (0)

#define DEBUG_FILENAME ("debuglog.dat")

FILE * debugFilePtr;

DEBUG( int boolSwitchFlag)

{

if (boolSwitchFlag==DEBUG_ON)

{

debugFilePtr = fopen(DEBUG_FILENAME,"w+");

}

if (boolSwitchFlag==DEBUG_OFF)

{

fclose(debugFilePtr);

}

}

// optionally, you can display date/time stamp with debug messages

#define DEBUG_LOG(str) (fprintf(debugFilePtr,str))

/********** end of debug.h *****************/

int main()

{

DEBUG(DEBUG_ON);

int iLoop=0;

char debugBuff[255];

for (iLoop=0; iLoop<10; iLoop++)

{

#ifdef _DEBUG

sprintf(debugBuff," Loop counter iLoop = %d \n",iLoop);

DEBUG_LOG(debugBuff);

#endif

printf(" Loop counter iLoop = %d \n",iLoop);

}

DEBUG(DEBUG_OFF);

}