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micro use in printf

#define WHITE BLACK

printf("WHITE");

is there any to print this output as-- BLACK.

this code i am using is in C.
Need urgent.
Thanks

You will have to change the code some.

Code:

#define WHITE    "BLACK"



...



printf( WHITE );

To my knowledge, there's no way to have the cpp modify the contents inside a string literal. That is, after all, the whole point. The programmer wants the literal text between the double quotes.

An alternative:

Code:

#include <stdio.h>

#include <string.h>



#define MACRO(str) (strcmp((str), "WHITE") ? (str) : "BLACK")



int main(void)

{

    printf( MACRO("WHITE") );

    printf("\n");

    return 0;

}

This kind of string substitution is used by e.g. the gettext() package, for internationalization. There, the macro is just _ , i.e. printf(_("WHITE"));

Note that the compiler does do some serious logic checking, so the above is not nearly as inefficient as one might think. At least gcc-4.6.1 on x86-64, even with -O0, compiles the above C to exactly the same code as

Code:

#include <stdio.h>



int main(void)

{

    printf("BLACK");

    putchar('\n');

    return 0;

}