How to shift a pointer by a few bytes?

Question

C++ / C#

malloc'om allocated memory, but I want to shift the pointer by 1 byte. How to do it?

Answer 1

int* a = malloc(len);
// ...
a = (int*)((char*)a + 1);

In char*, we add, back.

Answer 2

malloc'om allocated memory, but I want to shift the pointer by 1 byte. How to do it?

malloc allocates memory with sufficient alignment for all built-in data types. Shifting the pointer to such memory by 1 byte will spoil this alignment. The result, depending on the platform, will be slow access to this memory, alignment errors corrected by the OS kernel, or alignment errors leading to program termination.