How to add an integer to a pointer?
Add an integer to a pointer or subtract an integer from a pointer. The effect of p+n where p is a pointer and n is an integer is to compute the address equal to p plus n times the size of whatever p points to (this is why int * pointers and char * pointers aren’t the same). Subtract one pointer from another.
Which is the address of the next integer after PTR?
If ptr points to an integer, ptr + 1 is the address of the next integer in memory after ptr. ptr – 1 is the address of the previous integer before ptr. Note that ptr + 1 does not return the memory address after ptr, but the memory address of the next object of the type that ptr points to.
How to assign a value to a pointer?
The key is that the pointer is initialized to point to the variable. In fact, you could just allocate some raw memory to point to, if you want: #include <stdio.h> int main() { int *ptr; //Create a pointer that points to random memory address *ptr = 20; //Dereference that pointer, // and assign a value to random memory address.
How does pointer arithmetic work in C + +?
Pointer arithmetic The C++ language allows you to perform integer addition or subtraction operations on pointers. If ptr points to an integer, ptr + 1 is the address of the next integer in memory after ptr. ptr – 1 is the address of the previous integer before ptr.
Is it possible to convert an integer to a pointer?
However, they are not guaranteed to be long enough to hold a function pointer. Similarly, reinterpret_cast can be used to convert an integer type into a pointer type. Again the result is implementation-defined, but a pointer value is guaranteed to be unchanged by a round trip through an integer type.
How to store a pointer as an integer in C + +?
I’d say this is the modern C++ way. so the right way to store a pointer as an integer is to use the uintptr_t or intptr_t types. (See also in cppreference integer types for C99 ). these types are defined in for C99 and in the namespace std for C++11 in (see integer types for C++ ).
Can a pointer be cast back to an integer type?
The only guarantee is that a pointer cast to an integer type large enough to fully contain it (such as intptr_t ), is guaranteed to be able to be cast back to a valid pointer.
When to convert an int to an int in C + +?
If you want the “value” of the pointer, that is the actual memory address the pointer contains, then cast it (but it’s generally not a good idea) : If you need to get the value pointed-to by the pointer, then that’s not conversion.