About Macro

C or C++ is a language that one can always tweak to dig out something helpful but graceless. Below is an example I recently used to solve the problem of one of my colleagues. I think it is not astounding to sophisticated C programmers that macro can make so much trouble.

#include <stdio.h>

#define nameprint2(n) #n
#define nameprint(n) nameprint2(n)

#define name1() win
#define name2() dows
#define name() windows #define dotH() .h

#define cat3(a,b,c) a##b##c #define cat2(a,b) a##b

#define incname2 nameprint(cat2(name(),dotH()))

#define incname3 nameprint(cat3(name1(),name2()<wbr>,dotH()))<span></span> <span></span></wbr>

#include incname2 //#include incname3

int main (void)
{
char *p = incname2; HANDLE h; // this needs `windows.h' to be included

printf("%s/n", p);

return 0;
}