ebnf-terminal-regexp is a variable defined in `ebnf2ps.el'.
Its value is

Specify how it's a terminal name.

If it's nil, the terminal name must be enclosed by `"'.
If it's a string, it should be a regexp that it'll be used to determine a
terminal name; terminal name may also be enclosed by `"'.

It's used only when `ebnf-syntax' is `ebnf'.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 20 of Emacs.