🚀 go-pugleaf

Perhaps I'm confused but when I read the question this is what I came
up with.  It compiles and worked as expected in a test case.

As far as the two pointers to be swapped are concerned, they are of
the same type correct?

I do not see the problem with:

void swap_ptr(void **p1, void **p2) {
  void *tmp = *p1;

  *p1 = *p2;
  *p2 = tmp;

  return;
}


Granted I did not do an extensive test but I did try ints, chars and floats
with no surprises. As in:

#include <stdio.h>
#include"swap_ptr.h"

int main(void) {
  char c1='A', c2='B', *pc1, *pc2;
  int  i1=1, i2=2, *pi1, *pi2;
  float f1=1.1, f2=2.2, *pf1, *pf2;

  pc1 = &c1;
  pc2 = &c2;
  pi1 = &i1;
  pi2 = &i2;
  pf1 = &f1;
  pf2 = &f2;

  printf("%c , %c\n", *pc1, *pc2);
  swap_ptr(pc1, pc2);
  printf("%c , %c\n", *pc1, *pc2);

  printf("%d, %d\n", *pi1, *pi2);
  swap_ptr(pi1, pi2);
  printf("%d, %d\n", *pi1, *pi2);

  printf("%f, %f\n", *pf1, *pf2);
  swap_ptr(pf1, pf2);
  printf("%f, %f\n", *pf1, *pf2);

  return(0);
}

The output looks like:

r980(davidm)$ main
A , B
B , A
1, 2
2, 1
1.100000, 2.200000
2.200000, 1.100000
r980(davidm)$ 

Could someone enlighten me as to why this thread is so long?


Thanks
Dave