Bash bind command does not work correctly for interactive commands

Question

When I try bind some commands with bind -x bash utility, I can't see my stdin input on terminal.

Example:

root> # bind -x '"\C-p": su dargod'

When I type ctrl+P - I login to user dargod, but all what I types not shows. Same situation with bind ssh command for connect.

How I can normally interract with shell?

Info:

Bash 3.1.17 (CentOS 5)
Bash 4.2.46 (CentOS 7)
Bash 4.1.2 (CentOS 6)
Bash 5.0.7 (Arch Linux)
Bash 4.2.45 (Gentoo)

What is the info? Are those all the machines you have tried on or does your machine shift between operating systems and bash versions? — jesse_b, Aug 02 '19 at 20:45
Yes, In the info indicated on which systems I tried and with which versions bash — Dargod, Aug 02 '19 at 20:48

score 4 · Accepted Answer · edited May 26 '23 at 11:19

Commands bound to a key are meant to be used as part of line editing. They run with the terminal in raw mode without echo, with bash expecting to handle each key press¹. Most commands expect to run with the terminal in cooked mode, where the terminal reads one line at a time and echoes the input.

To run a command that takes over the terminal interaction, temporarily set the terminal to cooked mode.

bind -x '"\C-p": _bash_stty_save=$(stty -g); stty sane; su dargod; stty "$_bash_stty_save"'

Note that this may still not work perfectly, because you're doing something that bash doesn't expect. Bindings are not the right tool to run a command. To define a shortcut for a command, use an alias.

^{¹ strictly speaking, it's not a complete raw mode as ^C, ^Z,^\ (isig) and ^Q / ^S (ixon) are not disabled in bash' line editor (even though ^S conflicts with its emacs mode incremental search).}

Bash bind command does not work correctly for interactive commands

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