Sometimes, when I am typing really fast in bash, I accidentally do something and I get an underlined u diplayed at the prompt. After that, bash behaves strangely (I'm sorry, I can't remember what it does). I can never figure out what I pressed to enable the behavior. Usually I just have to resort to mashing keys to exit this mode. Can anyone tell me what's going on?
It's like you pressed
Ctrl-Shift-u. This will show an underlined
u indicating you can enter a hex code of a unicode character. It is not a bash specific feature, as it works in quite some apps.