On Sun, Mar 19, 2017 at 09:49:50AM +0100, Kai Krakow wrote > Hello! > > More and more of my Gentoo systems are exhibiting the following > strange and unexpected behavior: > > After ctrl+c'ing out of programs like tailf, SSH password prompts, in > the middle of a shell scripts, the shell echo is not restored - that > is: If I type characters I no longer see the characters (but they are > received and can be executed by "enter"). If experiencing this, I have > to ctrl+c again to discard what I was typing, the blindly type "reset" > to reset the terminal, then echo is enabled again.
"It's not a bug; it's a feature". It's caused by some programs. See http://askubuntu.com/questions/171449/shell-does-not-show-typed-in-commands-reset-works-but-what-happened for a detailed explanation. Executive summary... some programs, e.g. vim, can be run from the command line, and they accept certain control characters (CTRL-V, CTRL-I, etc) as valid input. These characters would normally be echo'd back to the user's terminal by the kernel's tty subsystem. This would foul up the application's screen display. To avoid that, the application turns off echoing to the tty when it starts up. It also restores echoing ***IF IT EXITS PROPERLY***. This also applies to when a program issues a password prompt, where you obviously want echoing turned off. If killed with CTRL-C or "kill -9" or "kill -15", it doesn't have a chance to restore echoing, and you get the situation you described. -- Walter Dnes <waltd...@waltdnes.org> I don't run "desktop environments"; I run useful applications
