Can you add pointers together? Why would you?
No, you can’t add pointers together. If you live at 1332 Lakeview Drive, and your neighbor lives at 1364
Lakeview, what’s 1332+1364? It’s a number, but it doesn’t mean anything. If you try to perform this type
of calculation with pointers in a C program, your compiler will complain
The only time the addition of pointers might come up is if you try to add a pointer and the difference of two
pointers:
p = p + p2 - p1;
which is the same thing as this:
p = (p + p2) - p1.
Here’s a correct way of saying this:
p = p + ( p2 - p1 );
Or even better in this case would be this example:
p += p2 - p1;
Cross Reference
VII.7: Can you subtract pointers from each other? Why would you?
No, you can’t add pointers together. If you live at 1332 Lakeview Drive, and your neighbor lives at 1364
Lakeview, what’s 1332+1364? It’s a number, but it doesn’t mean anything. If you try to perform this type
of calculation with pointers in a C program, your compiler will complain
The only time the addition of pointers might come up is if you try to add a pointer and the difference of two
pointers:
p = p + p2 - p1;
which is the same thing as this:
p = (p + p2) - p1.
Here’s a correct way of saying this:
p = p + ( p2 - p1 );
Or even better in this case would be this example:
p += p2 - p1;
Cross Reference
VII.7: Can you subtract pointers from each other? Why would you?
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