How to add characters to the end of char?

Question

C++ / C#

there is a program that works with processes
and here is a piece of code

char processname[64];
cout << "Введите процесс" << endl;
cin >> processname;

I need to add
something like .exe to what I entered

cout << "Введите процесс" << endl;
cin >> processname;
processname = processname + ".exe"

Of course, I understand that it doesn’t work like that, but still, how to add char to the end of char ?

Answer 1

Use memcpy().

Answer 2

C++ has had full-fledged (and therefore slow, but not in implementation, but ideologically) strings for a very long time, the string class with which and + will work and syntactically convenient

Answer 3

find where in processname '\0' and copy ".exe" there