[JdeBP]

Actually, no it isn't End-Of-File.

* http://jdebp.eu./FGA/dos-character-26-is-not-special.html

And SUB was ASCII's equivalent of U+FFFD.

[jacquesm]

Nice link, but even COMMAND.COM would see CTRL-Z as special, so I'm not sure why the author saw fit to make that claim, it's fairly well documented that plenty of DOS utilities did that and together with the core they make up the OS.