What is good practice for generating verbose output?

Question

what is good practice for generating verbose output? currently, i have a function

bool verbose;
int setVerbose(bool v)
{
    errormsg = \"\";
    verbose = v;
           


        

Answer 1

1. If you are using g++ you could use the -D flag, this allows the compilator to define a macro of your choice.

Defining the

For instance :

#ifdef DEBUG_FLAG
 printf("My error message");
#endif

2. I agree this isn't elegant either, so to make it a bit nicer :

void verbose(const char * fmt, ... )
{
va_list args;  /* Used as a pointer to the next variable argument. */
va_start( args, fmt );  /* Initialize the pointer to arguments. */

#ifdef DEBUG_FLAG
printf(fmt, &args);  
#endif
/*This isn't tested, the point is to be able to pass args to 
printf*/
}

That you could use like printf :

verbose("Error number %d\n",errorno);

3. A third solution easier, and more C++ and Unix like is to pass an argument to your program that is going to be used - as the macro earlier - to initialize a particular variable (that could be a global const).

Example : $ ./myprogram -v

if(optarg('v')) static const verbose = 1;