c++ - Typecast cross-platform compatibility -

What I'm trying to do is add a binary integer to a string object so far I have this:

  int number = 5; Cppstring.append ((* four *) and number, 4);  

It works well with Windows on an x86 system, but some people are saying that it is not cross-platform and is insecure. What is the most preferred way of doing this?

The reason for this is not portable that it is always 4 bytes For example, the ILP 64 data model uses 8-bytes. C99 only requires that at least 2 bytes are equal to why you need to do this, and what is the desired behavior if the size of the int is not 4 bytes?