private int
getChar() throws IOException {
	int c = is.read();
	if (c == '\r') {
		int next = is.read();
		if (next != '\n')
			is.unread(next);
		c = '\n';
	}
	if (c == '\n')
		line++;
	return c;
}
Creates a Tokenizer from a file.
@param f The File to tokenize.
src/main/java/core/org/xbill/DNS/Tokenizer.java