Text editor wrapping actual text - not display

I see text online and text files that have been wrapped to 80 chars wide however I cannot seem to find a text editor or function that 'maintains' the wrappin开发者_运维问答g to 80 characters - not just the appearance of the text but the actual text itself.

How do I do this in Notepad++? What about vim?

Thanks

The Zeus editor does this kind of hard line wrapping. There is a line wrap margin define in the Options, Properties menu.

Zeus is shareware, but there is a freeware Zeus Lite version that also has this feature.