Readline keymapping C-/ not working I have the following line in my `.inputrc` which does not appear to be working: "\C-/": insert-comment When I press `C-/` I expect the current line to be prefixed with the comment character (`#`) and executed, but when I press it nothing happens. If I change the keymapping to something like `\C-t` then it works fine. Why can't I use `C-/` as a keymapping?

The readline library follows the model of a physical terminal that could only transmit ASCII control characters and ANSI escape sequences. `C-/` is not an ASCII control character; the ASCII control characters are `c-@`, `C-a` .. `C-z`, `C-[`, `C-\`, `C-]`, `C-^`, `C-_`.