Among other things, I actually modified liner to stop using/swallowing all control codes, and to instead surface some of them to the client program to decide how to respond. e.g. liner stops doing anything with Ctrl-X (0x18 ?) and instead ng could respond to Ctrl-X by writing a docstring to stderr for an identifier under the caret in the input buffer.

https://github.com/frou/liner/blob/master/common.go#L208