[Adobe]generic swap macro in c

write a generic swap macro in c that can be used for swapping int ,char,float,double and even pointers.

AdminDecember 10, 2010 at 2:57 PM
void swap(void *a, void *b, size_t size)
{
char *ca, *cb;
int i;
ca = (char *)a;
cb = (char *)b;
for(i=0;i<size;*(ca+i)^=*(cb+i),*(cb+i)^=*(ca+i),*(ca+i)^=*(cb+i),++i);
}
void pointer can be used to store any kind of address,it is typecasted to char pointer so that one byte at a time can be swapped.
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AdminDecember 10, 2010 at 9:10 PM
/* Generic Swap macro*/
#define swap(a, b, type) { type t = a; a = b; b = t; }
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AdminDecember 14, 2010 at 4:09 PM
#define Swap(X,Y) { __typeof__ (X) T = X; X = Y; Y = T; }
int main()
{
int a=10,b=20;
Swap(a,b);
printf("%d %d",a,b);
return 0;
}

__typeof__ is a GNU C extension so we don't even need to pass type as third parameter.but it will be portability issue.
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AnonymousJanuary 26, 2012 at 5:56 AM
/* Generic Swap macro*/
#define swap(a, b, type) { type t = a; a = b; b = t; }

will not run .. try it... and try to find the reason :)
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