Why does cygwin mintty type 8~ (tilde) on its own?

Question

CYGWIN_NT-6.3 x86_64

I open and use a terminal (mintty) and every so often an

8~

or simply

~

will appear on the commandline.

Why does this happen and how do I prevent this from happening.

I mean in any output going to the terminal (startup scripts, prompt, whatever). — choroba, Dec 01 '15 at 17:03

score 4 · Answer 1 · answered Dec 01 '15 at 17:53

4

Found the cause.

I run a utility to keep my windows machine from going to sleep. In the background it creates an event for key-up for F15.

This has been transparent until using cywin.

answered Dec 01 '15 at 17:53

Barry

2

I've discovered the same issue on my machine. I am running a tool called 'caffeine' that keeps my machine awake. – Bill D Nov 01 '16 at 13:17

mach · Answer 2 · 2020-11-26T16:28:12.343

If the utility that is causing this input is Caffeine sending a F15 key up event, you can prevent it from happening in two ways:

Prevent F15 from being interpreted on the mintty side: Add the following line to your mintty config file (e.g. ~/.minttyrc). It tells mintty to ignore F15 by itself or with the Ctrl modifier, which does the trick for me (by itself, it produces ~, and with Ctrl, ;5~):
```
KeyFunctions=F15:void;C+F15:void
```
Prevent Caffeine from sending F15 by running it with the -useshift option.

I guess the first way is preferrable, because it keeps all the benefits of using the F15 key up event.

2 Answers2