C++ : Confusion between Copy & Assignment

According to "C++ Primer, 5th Ed.", section 8.1.1:

ofstream out1, out2;
out1 = out2;              // error: cannot assign stream objects
// print function: parameter is copied
ofstream print(ofstream); // error: can't initialize the ofstream parameter
out2 = print(out2);       // error: cannot copy stream objects -- Line 4

Line 4 says "cannot copy stream objects". Is it implying on the print() command on line 4, or the =, that a copy is not permitted? The = to me is the assignment statement while the print(out2) is calling the constructor of ofstream passing the out2 argument. So I'm a bit confused here.

Can anyone explain better?