Why do my keystrokes turn into crazy characters after I dump a bunch of binary data into my terminal?

Question

If I do something like:

$ cat /bin/ls

into my terminal, I understand why I see a bunch of binary data, representing the ls executable. But afterwards, when I get my prompt back, my own keystrokes look crazy. I type "a" and I get a weird diagonal line. I type "b" and I get a degree symbol.

Why does this happen?

Answer 1

Because somewhere in your binary data were some control sequences that your terminal interpreted as requests to, for example, change the character set used to draw. You can restore everything to normal like so:

reset

Answer 2

Just do a copy-paste:

echo -e '\017'

to your bash and characters will return to normal. If you don't run bash, try the following keystrokes:

<Ctrl-V><Ctrl-O><Enter>

and hopefully your terminal's status will return to normal when it complains that it can't find either a <Ctrl-V><Ctrl-O> or a <Ctrl-O> command to run.

<Ctrl-N>, or character 14 —when sent to your terminal— orders to switch to a special graphics mode, where letters and numbers are replaced with symbols. <Ctrl-O>, or character 15, restores things back to normal.