Another neat thing I noticed while playing with it just now: there's an option to enter ~ twice to send a literal ~, but usually you don't have to do this when typing something like 'ls ~' in a regular session. Not only does the ~ have to be the first character on a line to start an escape sequence, but typing on a line, backspacing all the way to the start and then typing ~ also sends a literal tilde. It only triggers the escape sequence if the ~ is the chronologically first character after a newline (or first in the session), which is an unlikely thing to type into a shell in a normal session. Good choice of UI, both the character and the state machine.

"It's easier to ask an AI" can be true without implying that manpages are bad.

However, "man" the tool does have issues, and one of them bit me just now.

So, I didn't know about openssh client escapes like ~?. I thought, "surely that's in the manpage?" I opened the manpage (in less) and searched for "\~\?". No hits.

Of course, escape characters are documented in the manpage, and the string "~?" does appear. Why didn't search find it? Because man, in its infinite wisdom, decided to render every instance of "~" as some bizarre unicode not-tilde, which is visually similar but totally impossible to grep for.

This has also bitten me in the past with dash. DASH. A character that is critically important when documenting invocation options. man loves to convert it into something that looks like dash, prints like dash, but doesn't come up in search.

I'm sure there is a way to turn this "feature" off, and I'm about to spend a bunch of time figuring out what it is. But this is documentation for command-line tools. Silently destroying our ability to grep it should NOT be the default.

Anyway, if you try it from shell prompt it is likely will not work as pressing ENTER shows the next prompt. Try `cat` followed by ENTER and then ~?

    Host *
      ControlMaster auto
      ControlPath ~/.ssh/sockets/%r@%h:%p
      ControlPersist 10m

This pairs well with the ~C escape discussed here: adding a port forward mid-session via ~C -L 8080:localhost:8080 doesn't require a new connection or re-authentication when a ControlMaster is already running. Useful for those "I need to tunnel something I didn't anticipate" moments.

I guess you could call it a "secret" or at least "not super-well known (to people who aren't Linux 'experts')."

The good old times!

What I now have: ~B

What I really need: a way to stop long-running SSH connections from freezing

~.

I really hate it when people just rename terms. It made it harder to search properly for better answers.

I find it convenient not to have to worry about accidentally entering escape characters. YMMV.

I use it when I need to crash a kernel on purpose to test kdump over the network.

You can also send commands to the simulated console of a VM under libvirt with "virsh connect". But I don't think you can send a break to the kernel with that.

https://xkcd.com/1053/

    $ man ssh