How do I kill a (command line) app that's hanging?

Ok you're instinct is to say Ctrl-c. That's not working.

I'm running alpine, and it's stuck trying to send an email. So how do I kill it?

This is in runlevel 3, so there's no GUI here. I can't just open another terminal window; there are no windows.

I can't run top or ps to get it's id and kill it, because I don't have a command line besides this one, and it's stuck in alpine.

Ctrl-c isn't doing anything. What's left to do besides restart? I really don't want to restart and I doubt I need to but I don't know how to kill it if Ctrl-c isn't working.

It's an unusual situation, right. A conundrum.

Perhaps you should read up on using virtual terminals. Opening another may not help with the recalcitrant alpine though, depending on how it is "hung".

1 members found this post helpful.

I love you! That was brilliant, I opened a new terminal, found the PID, and killed it. Brilliant, thanks syg00

in general you can use Ctrl-Z to suspend the current job. Next execute bg to put that process into background and run kill <signal> %1 to kill it.

you can use pgrep and pkill also to find/kill a process.

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Oh that's a good idea, I didn't think of trying Ctrl Z and then bg. I have a feeling it probably wouldn't have responded to Ctrl Z if it wasn't responding to Ctrl C.

And to get the pid, I did:

ps | grep "alp" from the other virtual terminal, and then just "kill <pid>". and then I switched back to the first one. woo! I love this stuff...

I didn't know about pgrep and pkill. I learned a lot here, if anyone else reads this thread, maybe this might be useful:

https://www.computerhope.com/unix/upgrep.htm

I forgot about HUP, and I also learned that nice has levels. That makes sense. I always just used nice with it's default settings.

Anyway thanks guys, long live linux.

Sometimes programs are so severely stuck that you have to force a kill. Then the program itself does not terminate, but the OS kicks it out of the execution queue.
Use it only when else is not possible. The terminated program does not release its resources. If you do it often you'll be out of resources sooner or later and must reboot.

In Linux we call applications programs or tasks. Not apps. That is for iShit and Windows.

jlinkels

if ctrl-c doesn't do it, try ctrl-d.
and sometimes it just takes a while until the prompt returns.

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I use either gnome-system-monitor or as others have stated...

Right, but as I said, I didn't have a command line. I know how to use kill and ps | grep <name>

But I couldn't get to a command line. You see? (See original post.)

It was syg00's advice that got me to a command line, which is awesome and so relieving.

^ My apologies. I should have read your post more closely.

Hey I wanna also point out, (and I'm embarrassed to say this),

I realized that when I installed, (this is a fresh install), I had ticked the checkbox to include an ssh server. So I realized wait, I can just ssh in and that's just the same as another terminal window.

Just thought I'd mention that in case anyone else has the same problem,

rw