Writing TXT File with PHP, Want to Add an Actual Line Break

[gsmorbit.com]

I am writing a TXT file using PHP. I want to insert actual line breaks into the TXT file wherever necessary. I have tried all combinations of \n \r \r\n \n\r ... but these are not causing any linebreaks to appear - in most cases, I am seeing the text "\n" appear in the TXT file, with no linebreak.I have also tried chr(13).Any other ideas would be appreciated.