On Mon, Jan 27, 2020 at 09:03:22PM -0500, Roger wrote: > I've always had a problem with Bash script (eg. for/while) loops creating > havoc > upon a ctrl-c keypress.
What's *in* the loop? It matters. Consider the following two scripts: ================================== #!/bin/bash while true; do echo "Zzz" sleep 1 done ================================== ================================== #!/bin/bash while true; do # Assuming Linux ping -c 1 8.8.8.8 done ================================== If you run these, and try to kill them with Ctrl-C, you may find that the first one behaves perfectly (stops when you ask), and the second one does not. It may take several tries to kill the second one. You might have better luck suspending it with Ctrl-Z first, then killing the shell only, then fg'ing the job. See <https://www.cons.org/cracauer/sigint.html> for details. In a nutshell, ping(8) is a misbehaving program. It sets a SIGINT trap (so that it can report statistics when you interrupt it), but it doesn't exit as a result of the signal. The shell sees that the program didn't exit due to SIGINT, and decides that it (the shell) should not exit either. Whatever program you're using inside your loop may have the same issues. It's extremely common.
