Question

I am a beginner for C++ so I’m sorry if this question sounds stupid..

I made this little program to help me get familiar with the properties of cin:

#include <iostream>
#include <string>
using namespace std;

int main()
{
    string next;
    cout<<"Enter your input.\n";
    cin>>next;
    cout<<next;
    return 0;
}

When I typed in \n from the keyboard input, I was returned \n.

Also, when I changed the variable next from a string to a character and gave it the same input as above, I was returned only a \.

My question is: Why am I not returned with a new line instead? Doesn’t cin recognize \n type in from keyboard as a newline character? Or is it just applicable to cout?

Answer 1

\n is an escape sequence in C++; when it appears in a character constant or a string literal, the two character sequence is replaced by the single character representing a new line in the default basic encoding (almost always 0x0A in modern systems). C++ defines a number of such escape sequences, all starting with a \.

Input is mapped differently, and in many cases, depending on the device. When reading from the keyboard, most systems will buffer a full line, and only return characters from it when the Enter key has been pressed; what he Enter key sends to a C++ program may vary, and whether the file has been opened in text mode or binary mode can make a difference as well—in text mode, the C++ library should negotiate with the OS to ensure that the enter key always results in the single character represented by \n. (std::cin is always opened in text mode.) Whether the keyboard driver does something special with \ or not depends on the driver, but most don’t. C++ never does anything special with \ when inputting from a keyboard (and \n has no special meaning in C++ source code outside of string literals and character constants).