Void * precautions for addition and subtraction of pvoid.

When the parameter provided by a function is void *, pointer operations such as + 1 and-1 depend on the type of the actual variable.

For example. Memcpy function,

Void*Memcpy (
Void * Dest,
Const void * SRC,
Size_t Count
);

We can see that parameter 1 and 2 are all void *.

Assume char * pdest; char * psrc; int nstrlen;

Then memcpy (pdest, psrc + 1, nstrlen)

, The psrc pointer will add the sizeof (char) * nstrlen bytes.

Similarly, if lpwstr pwdest, lpcwstr pwsrc; int nstrlen;

Memcpy (pwdest, pwsrc + 1, nstrlen)

The pointer of pwsrc is added with sizeof (wchar) * nstrlen bytes.