More Exceptional C++

Chapter 1. Switching Streams

Difficulty: 2

What's the best way to dynamically use different stream sources and targets, including the standard console streams and files?

1. What are the types of std::cin and std::cout?

2. Write an ECHO program that simply echoes its input and that can be invoked equivalently in the two following ways:

   ECHO <infile >outfile
   
   ECHO infile outfile
   

   In most popular command-line environments, the first command assumes that the program takes input from cin and sends output to cout. The second command tells the program to take its input from the file named infile and to produce output in the file named outfile. The program should be able to support all of the above input/output options.

Solution

• 1. What are the types of std::cin