So how can I close the terminal where the process is in with killall.
I have tried this:
In 1st terminal:
killall node
In 2nd terminal:
Ready
Terminated
But I want only the 2nd terminal to close after the node is killed.
You can use the -t option:
killall -t $(tty)
will call all processes started from the terminal session (even with nohup), including the shell. So, your terminal will get closed.
You need to also kill the process which runs the terminal, which is usually the parent process of the node process.
The question How do I get the parent process ID of a given child process? is a good place to start. You can find the PIDs of the node processes via How to find the Process ID of a running terminal program.
Related
Open a terminal
Open the second terminal
Excute command "$ xlogo" in the sceond terminal
Find out the parent process of xlogo in the first terminal
(I find out that "bash" is the parent process)
Terminate the parent process of xlogo in the first terminal
(Command:$ kill -9 PID of parent process)
At this moment, "xlogo" and the second terminal are gone.
Open the third terminal.
Excute the command "$ xlogo &" in the third terminal (Let xlogo running in the background)
Teminate the parent process of xlogo in the first
terminal
(Command:$ kill -9 PID of parent process)
At this moment, "xlogo" still alive, but the third terminal is gone.
By excuting the command "$ pstree", I find that "xlogo" belongs to "systemd".
Questions:
a) Why "xlogo" was killed with its parent process when "xlogo" ran in the foreground?
b) Why "xlogo" still alive and didn't die with its parent process when "xlogo" ran in the background?
I am searching for a long time on the net. But get nothing.
Could anyone try to give some ideas on how to explain this?
thx
I have a bash script:
node web/dist/web/src/app.js & node api/dist/api/src/app.js &
$SHELL
It successfully starts both my node servers. However:
I do not receive any output (from console.log etc) in my terminal window
If I cancel by (Ctrl +C) the processes are not exited, so then I annoyingly have to manually do a taskkill /F /PID etc afterwards.
Is there anyway around this?
The reason you can't stop your background jobs with Ctrl+C is because signals (SIGINT in this case) are received only by the foreground process.
When your foreground process (the non-interactive main script) exits, its children processes become orphans which are immediately adopted by the init process. To kill them, you need their PIDs. (When you run a background process in an interactive shell, it will receive the SIGHUP, and probably exit, when shell exits.)
The solution in your case is to make your script wait for its children, using the shell built-in wait command. wait will ensure your script receives the SIGINT, which you can then handle (with trap) and kill the background jobs (with kill 0):
#!/bin/bash
trap 'kill 0' EXIT
node app1.js &
node app2.js &
wait
By setting trap on EXIT (special pseudo-signal in bash), you'll ensure background processes will terminate whenever your main script exits (either by Ctrl+C/SIGINT, or by any other signal like SIGTERM, SIGHUP, SIGKILL). The kill 0 command kills all processes in the current process group.
Regarding the output -- on Linux, background processes will inherit the standard output/error from shell (if not redirected), and continue to write to your TTY/terminal. If that's not working on Windows, I'm not sure why not.
However, even if your background processes somehow lost their way to your TTY, you can, as a workaround, append to a log file:
node app1.js >>/path/to/file.log 2>&1 &
node app2.js >>/path/to/file.log 2>&1 &
and then tail -f that log file, either in this, or some other terminal:
tail -f /path/to/file.log
I run a few processes that I created myself on my Ubuntu Server, and to kill them I run:
sudo fuser -n tcp PORT
kill -9 PID-DISPLAYED
Is there any way I can obtain the PID from a port using a shell script, then kill it by running the shell script.
Thanks.
fuser can kill it:
-k, --kill
Kill processes accessing the file. Unless changed
with -SIGNAL, SIGKILL is sent. An fuser process
never kills itself, but may kill other fuser processes.
The effective user ID of the process executing fuser is
set to its real user ID before attempting to kill.
Try using either killall, or pkill, either of which will close all processes of the type of argument you describe, for example:
killall firefox
Will kill all running instances of firefox.
See
this link of pkill.
Well, I'm basically trying to make a bash script runs a node script forever. I made the following bash script:
#!/bin/bash
while true ; do
cd /myscope/
unlink nohup.out
node myscript.js
sleep 6
done & echo $! > pid
I'm expecting that when it runs, it starts up node with the given script, checks if node exits, sleeps for 6 seconds if so and reopen node. Also, I'm expecting it to run in background and writes it's pid (the bash pid) on a file called "pid".
Everything explained above works as expected, apparently, but I'm also expecting that when the pid of the bash script is killed, the node script would stop running, I don't know why that made sense in my mind, but when it comes to practice, it doesn't work. The bash script is killed indeed, but the node script keeps running and that is freaking me out.
I've tested it in the terminal, by not sending the bash script to the background and entering ctrl+c, both scripts gets killed.
I'm obviously miss understanding something on the way the background process works. For god sake, can anybody help me?
There are lots of tools that let you do what you're trying, just two off the top of my head:
https://github.com/nodejitsu/forever - A simple CLI tool for ensuring that a given script runs continuously (i.e. forever)
https://github.com/remy/nodemon - Monitor for any changes in your node.js application and automatically restart the server - perfect for development
Maybe the second it's not what you're looking for, but still worth a look.
If you can't or don't want to use those then the problem is that if you kill the parent process the child one is still there, so, you should kill that too:
pkill -TERM -P $PID
where $PID is the parent PID.
I have a script started in a screen session, then detached, tried to reattach but now this session is dead.
The script is still running.
How I can kill the script, being unable to reattach the screen session?
Unfortunatly I have killed the screen process shown with ps.
Is there any possibility to stop the script?
I assume you are in a linux enviroment, as you say you used ps. If you have the uuid of the process, you can kill it by using kill < uuid> -9. If you know the process by name, try pkill < name>. Both cases should work on a terminal. If you are unable to open a terminal, try ctrl+alt+f1. You should see a login prompt, followed by a terminal. To get back to the xsession do ctrl+alt+f7
If everything else fails, try killing all processes: kill -9 -1. This should get you back to your display manager.
If you killed your screen process, try xinit from a terminal and then try to go back.
If you can't see the process, try ps aux