Is there anything for getting right end-of-line symbol for any platform? I mean, I can use \\n for Windows and Unix if I want to write EOL to file, but there is
When you are writing a file in text mode, the "\n" character should be reinterpreted as whatever is appropriate for that system. For Windows, that means CRLF (carriage return, line feed), on Unix, it's just LF alone, and the Macintosh standard is a CR by itself.
When you are reading, be ready to end a line at either one of those characters, but if you find a carriage return, check to see if there is a line feed immediately after it, and if there is, consider it part of the same line.