C ++ - 字符串中的跨平台换行符

Question

When newline in string is necessary, I use the \n character

 int main()
 {
     string str = "Hello world\n";
 }

Is \n crossplatform? Or do I need to use macro adapting it's value with the platform?

Especially when str is going to be written to a file or stdout.

Answer 1

As long as you read/write text streams, or files in text mode, \n will be translated into the correct sequence for the platform.

http://en.cppreference.com/w/c/io

Answer 2

In addition on previous answer if you need read file in Unix saved in Windows and vice-versa you may use this:

std::getline(fileName,inputStr);
inputStr.erase( std::remove( inputStr.begin(), inputStr.end(), '\r' ), inputStr.end() );
inputStr.erase( std::remove( inputStr.begin(), inputStr.end(), '\n' ), inputStr.end() );

It will delete all \r and \n .

Answer 3

Another way to put it is that \n is cross platform for the compiler. It will compile on all platforms and generate correct output for the platform. But the output is not really cross platform since new line in text is different on different platforms. So reading need extra handling to be platform independent.

Answer 4

Part of the confusion here is that a string with an \n in it is literally just that - a string with an LF byte.

The cross-platformyness comes into the equation when considering the reading and writing of streams in normal ie not binary mode.

Stream objects translate \n to \n , \r or \r\n depending on the platform the executable code has been compiled for.

At least this is my understand of the situation, please correct me if I am wrong about this. It isn't something I have had to worry about much in the past, since I usually exclusively write code for Linux systems.

Thought I should add this since the question doesn't really make sense, although I get what you are asking.