I call this in my local machine
ssh -t anon#192.168.50.81 -p 10086 'echo $SHELL && pstree'
I got /bin/zsh and a normal pstree output without shell process.
Why? And is the first output a fake one?
Some shells, like zsh, do not fork a child process to execute the last command in a command line or script. Since the exit status of the line or script is the same as the exit status of the last command, they call exec() in the shell process without forking. So if you execute
sleep 5 && pstree
it will fork a child for sleep, wait for it to finish, then call exec() to run pstree.
Since the pstree process replaces the shell, you don't see the shell in the process tree. pstree will be the child of sshd.
If you change it to
pstree && sleep 5
then you should see the shell in the pstree output, because pstree is no longer the last command.
If I have process named raspivid and process named raspivideo running and I execute command pkill raspvid, does it kill both processes or only process which is named raspvid?
If pkill kills both processes is there any linux-command to do the perfect match?
pkill kills all processes that command pgrep lists with the same parameters. In your case it sends SIGTERM signal to both processes.
The following command kills the exactly matching pattern only:
pkill -x raspivid
I run a shell script inside php (using shell_exec). I want to kill it and all processes it created when it is in operation. I know the shell script pid. Do you have any suggestion?
I am using ubuntu, php as apache module.
Thank you.
Example:
#!/bin/bash
echo hello
sleep 20
When I kill my script (shell_exec("sudo kill -9 $pid")), the sleep process is not killed which is not desired.
use
pkill -TERM -P pid
will kill the child processes
see this answer
Use this kill command instead:
kill -- -$pid
to kill the running script and all its spawned children.
The command kill $$ should kill current bash, but it seems that it doesn't work:
$ ps -p $$
PID TTY TIME CMD
18179 pts/4 00:00:00 bash
$ kill $$
$ ps -p $$
PID TTY TIME CMD
18179 pts/4 00:00:00 bash
Why?
I'm not sure why one would like to kill the current shell. Nevertheless...
kill PID would send SIGTERM when no signal is specified. bash ignores SIGTERM and SIGQUIT in the absence of any traps.
You'll achieve the desired effect if you were to say
kill -9 $$
or
kill -SIGKILL $$
Quoting from the manual:
When Bash is interactive, in the absence of any traps, it ignores
SIGTERM (so that ‘kill 0’ does not kill an interactive shell), and
SIGINT is caught and handled (so that the wait builtin is
interruptible). When Bash receives a SIGINT, it breaks out of any
executing loops. In all cases, Bash ignores SIGQUIT.
When you send a process any signal using kill command, the process can choose to handle the signal as per its wish. (There are a few signals, which cannot be handled.)
When you use kill $$, you are actually passing it signal=15 (SIGTERM). It can be handled by a process.
You can google for linux signal example to know HOW it is implemented.
& To answer YOUR question:
If you pass an un-handlable signal, like SIGKILL(9) or SIGSTOP(19), it will respectively kill/stop a running bash process.
I'm running a nohup process on the server. When I try to kill it my putty console closes instead.
this is how I try to find the process ID:
ps -ef |grep nohup
this is the command to kill
kill -9 1787 787
When using nohup and you put the task in the background, the background operator (&) will give you the PID at the command prompt. If your plan is to manually manage the process, you can save that PID and use it later to kill the process if needed, via kill PID or kill -9 PID (if you need to force kill). Alternatively, you can find the PID later on by ps -ef | grep "command name" and locate the PID from there. Note that nohup keyword/command itself does not appear in the ps output for the command in question.
If you use a script, you could do something like this in the script:
nohup my_command > my.log 2>&1 &
echo $! > save_pid.txt
This will run my_command saving all output into my.log (in a script, $! represents the PID of the last process executed). The 2 is the file descriptor for standard error (stderr) and 2>&1 tells the shell to route standard error output to the standard output (file descriptor 1). It requires &1 so that the shell knows it's a file descriptor in that context instead of just a file named 1. The 2>&1 is needed to capture any error messages that normally are written to standard error into our my.log file (which is coming from standard output). See I/O Redirection for more details on handling I/O redirection with the shell.
If the command sends output on a regular basis, you can check the output occasionally with tail my.log, or if you want to follow it "live" you can use tail -f my.log. Finally, if you need to kill the process, you can do it via:
kill -9 `cat save_pid.txt`
rm save_pid.txt
I am using red hat linux on a VPS server (and via SSH - putty), for me the following worked:
First, you list all the running processes:
ps -ef
Then in the first column you find your user name; I found it the following three times:
One was the SSH connection
The second was an FTP connection
The last one was the nohup process
Then in the second column you can find the PID of the nohup process and you only type:
kill PID
(replacing the PID with the nohup process's PID of course)
And that is it!
I hope this answer will be useful for someone I'm also very new to bash and SSH, but found 95% of the knowledge I need here :)
suppose i am running ruby script in the background with below command
nohup ruby script.rb &
then i can get the pid of above background process by specifying command name. In my case command is ruby.
ps -ef | grep ruby
output
ubuntu 25938 25742 0 05:16 pts/0 00:00:00 ruby test.rb
Now you can easily kill the process by using kill command
kill 25938
jobs -l should give you the pid for the list of nohup processes.
kill (-9) them gently.
;)
You could try
kill -9 `pgrep [command name]`
Suppose you are executing a java program with nohup you can get java process id by
`ps aux | grep java`
output
xxxxx 9643 0.0 0.0 14232 968 pts/2
then you can kill the process by typing
sudo kill 9643
or lets say that you need to kill all the java processes then just use
sudo killall java
this command kills all the java processes. you can use this with process. just give the process name at the end of the command
sudo killall {processName}
If your application always uses the same port, you can kill all the processes in that port like this.
kill -9 $(lsof -t -i:8080)
This works in Ubuntu
Type this to find out the PID
ps aux | grep java
All the running process regarding to java will be shown
In my case is
johnjoe 3315 9.1 4.0 1465240 335728 ? Sl 09:42 3:19 java -jar batch.jar
Now kill it kill -9 3315
The zombie process finally stopped.
when you create a job in nohup it will tell you the process ID !
nohup sh test.sh &
the output will show you the process ID like
25013
you can kill it then :
kill 25013
I started django server with the following command.
nohup manage.py runserver <localhost:port>
This works on CentOS:
:~ ns$netstat -ntlp
:~ ns$kill -9 PID
This works for mi fine on mac
kill -9 `ps -ef | awk '/nohup/{ print \$2 }'`
I often do this way. Try this way :
ps aux | grep script_Name
Here, script_Name could be any script/file run by nohup.
This command gets you a process ID. Then use this command below to kill the script running on nohup.
kill -9 1787 787
Here, 1787 and 787 are Process ID as mentioned in the question as an example.
This should do what was intended in the question.
If you are unaware of the PID, then first find it using TOP command
top -U userid
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
You will get the PID using top, then perform the kill operation.
$ kill -9 <PID>
Today I met the same problem. And since it was a long time ago, I totally forgot which command I used and when. I tried three methods:
Using the STIME shown in ps -ef command. This shows the time you start your process, and it's very likely that you nohup you command just before you close ssh(depends on you) . Unfortunately I don't think the latest command is the command I run using nohup, so this doesn't work for me.
Second is the PPID, also shown in ps -ef command. It means Parent Process ID, the ID of process that creates the process. The ppid is 1 in ubuntu for process that using nohup to run. Then you can use ps --ppid "1" to get the list, and check TIME(the total CPU time your process use) or CMD to find the process's PID.
Use lsof -i:port if the process occupy some ports, and you will get the command. Then just like the answer above, use ps -ef | grep command and you will get the PID.
Once you find the PID of the process, then can use kill pid to terminal the process.
About losing your putty: often the ps ... | awk/grep/perl/... process gets matched, too! So the old school trick is like this
ps -ef | grep -i [n]ohup
That way the regex search doesn't match the regex search process!
if you are on a remote server, check memory usage with top , and find your process and its ID. After that, just execute kill [your process ID] .