Thread: Comparing pointers

You can compare to see if they point at the same location.

Code:

int* p1, p2;

if ( p1 == p2 )

Or you could compare to see if the value at whatever location they point at, equals.

Code:

int* p1, p2;

if ( *p1 == *p2 )

If the pointers point to the elements of the same array (or one past the end thereof) or aggregate (typically a struct object), then you can also use the relational operators (<, <=, >, >=) to compare for their relative locations.

By the way, Ktulu's post #2 has a common typo error with respect to declaring pointers. This:

Code:

int* p1, p2;

declares p1 to be a pointer to int and p2 to be an int, whereas this:

Code:

int *p1, *p2;

declares both p1 and p2 to be of type int.

To avoid this kind of mistake, I suggest that you declare them separately:

Code:

int *p1;
int *p2;

or equivalently:

Code:

int* p1;
int* p2;

Originally Posted by laserlight

whereas this:

Code:

int *p1, *p2;

declares both p1 and p2 to be of type int.

should be "of type pointer-to-int."