Using Vi

1. Open the file in Vi editor
2. Switch to command mode.
3. To replace all newline characters with comma use
   :1,$s/\n/, /g
4. Press Enter

---

Using NotePad++

1. Open a NotePad++ window.
2. Insert Find and Replace mode.
3. Within the Find What field, enter the following:
   \r\n
4. Within the Replace with field, enter a comma.