How to read until EOF from cin in C++

c++ input iostream
Guille picture Guille · Oct 14, 2008 · Viewed 219.5k times · Source

I am coding a program that reads data directly from user input and was wondering how could I (without loops) read all data until EOF from standard input. I was considering using cin.get( input, '\0' ) but '\0' is not really the EOF character, that just reads until EOF or '\0', whichever comes first.

Or is using loops the only way to do it? If so, what is the best way?

Answer

trotterdylan picture trotterdylan · Oct 14, 2008

The only way you can read a variable amount of data from stdin is using loops. I've always found that the std::getline() function works very well:

std::string line;
while (std::getline(std::cin, line))
{
    std::cout << line << std::endl;
}

By default getline() reads until a newline. You can specify an alternative termination character, but EOF is not itself a character so you cannot simply make one call to getline().

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