How to convert to/from DOS format in VIM…

It’s very easy, but also easy to forget how to convert to or from a DOS format file in Unix using “vim” (Vi iMproved), the Open Source “vi”. If the file is in DOS format and you want to convert to Unix, use the command:

:set ff=unix

note that “ff” is an abreviation for “fileformat” which you can also use.

If the file is Unix and you want to write DOS format, use the following command:

:set ff=dos

In both examples it is assuming you are ESCaped out of edit mode and the leading “:” is required.

Note that the difference between the two formats is that:

• DOS format ends each line with a CRLF (carriage-return line-feed) pair.
• Unix format ends each line with a simple LF (line feed).

Neither of these forms should be confused with the C language string delimiter ‘NUL’ which is an ASCII “zero”. That however is an entirely different subject.