Find out if process / file is running linux - linux

I want to check if a process is running or not. I've been trying by
ps -C /path/file
and get this response:
PID TTY TIME CMD
If I do
pgrep php
I get a list of php processes running, but only the PID.
Is there a possibility to
determine the PID of a file I specify (I want to type the file and get the PID)
get the filename if I type the PID
get all the running processes PIDs in a file to work with that in a later script
OS: Ubuntu 14.04 LTS
I've been looking for this since quite some time, tried all the possibilities I found on SO and else but just can't figure out how to do this best.

"Determine the PID of a file I specify."
lsof | grep <file> | awk '{print $2}'
"Get the filename if I type the PID."
lsof | grep <PID>
lsof | grep <PID> | awk '{print $NF}'
"Get all the running processes PIDs in a file to work with that in a later script."
ps x | awk '{print $1}' > pid-list.txt # PIDs of all processes run by current user
ps ax | awk '{print $1}' > pid-list.txt # PIDs of all processes run by all users

What about ps aux | grep <the-name-of-the-process>.

Related

.bashrc saves previous process id and does not update in alias commands

I have made an alias in .bashrc to kill my python service.py & process
alias servicestop="kill $(ps -ef | grep -w service.py | grep -v grep | awk '{print $2}')"
Whenever I run first time servicestop command it will kill the process.
but again whenever I start process python service.py &, and execute command servicestop it gives an error.
After research, I found following things.
when I run first time python service.py & process. its process id was 512.
and, command servicestop kill that process(512).
Now when I run Second time process python service.py &. its process id was 546.(definitely it will be different).
When I run command servicestop. it will give following error:
-bash: kill: (512) - No such process
That means $(ps -ef | grep -w service.py | grep -v grep | awk '{print $2}') will return the previous pid, which is already killed.
Now please suggest the solution if any possible.
so whenever I want to run servicestop command, I have to run source .bashrc command first, then run servicestop command to make it work.
Please remove the servicestop alias from your .bashrc and add :
servicestop(){
kill $(ps -ef | grep -w service.py | grep -v grep | awk '{print $2}');
}
In a way, functions in .bashrc are "aliases 2.0" : simply better
Better : same function; but with the name of script to kill as parameter :
servicestop(){
kill $(ps -ef | grep -w $1 | grep -v servicestop | awk '{print $2}');
}
Use it like that :
servicestop service.py
servicestop otherSuperService.py

how can I kill a process in a shell script

My bash script has:
ps aux | grep foo.jar | grep -v grep | awk '{print $2}' | xargs kill
However, I get the following when running:
usage: kill [ -s signal | -p ] [ -a ] pid ...
kill -l [ signal ]
Any ideas, how to fix this line?
In general, your command is correct. If a foo.jar process is running, its PID will be passed to kill and (should) terminate.
Since you're getting kill's usage as output, it means you're actually calling kill with no arguments (try just running kill on its own, you'll see the same message). That means that there's no output in the pipeline actually reaching xargs, which in turn means foo.jar is not running.
Try running ps aux | grep foo.jar | grep -v grep and see if you're actually seeing results.
As much as you may enjoy a half dozen pipes in your commands, you may want to look at the pkill command!
DESCRIPTION
The pkill command searches the process table on the running system and signals all processes that match the criteria
given on the command line.
i.e.
pkill foo.jar
Untested and a guess at best (be careful)
kill -9 $(ps -aux | grep foo.jar | grep -v grep | awk '{print $2}')
I re-iterate UNTESTED as I'm not at work and have no access to putty or Unix.
My theory is to send the kill -9 command and get the process id from a sub shell command call.

grepping the PID of a process - Unix

I'm trying to execute the following command:
ps aux | grep com.scheduler.app.workermain | kill -15 [pid]
How can I obtain the [pid] (or list of PID) using ps aux | grep "expression" and pipe that to kill? There may be zero or many processes running the machine. This is part of an automated job, to ensure all the processes spun will be terminated.
A sample line from the command line, when ps aux | grep com.scheduler.app.workermain is executed is:
jenkins 12373 1.1 4.2 2905440 173628 ? Sl 19:28 0:05 java -Xmx600m -Dlog4j.configurationFile=log4j2-trace.xml -Dpid=foobar -Dipaddr=127.0.0.1 -cp build/classes:build/dependency/* com.scheduler.app.workermain testing.properties
pkill is used for exactly this purpose. How about:
pkill -15 -f com.scheduler.app.workermain
Also if you just want to grep for a PID you can use pgrep:
pgrep -f com.scheduler.app.workermain
pkill man page
kill -15 $(ps aux | grep -i com.scheduler.app.workermain | awk -F' ' '{ print $2 }')
One of possible solutions is to use the pidof command:
kill $( pidof com.scheduler.app.workermain )
PS. You don't need to pass -15 (or -TERM) to the kill command, as SIGTERM is the default signal sent.

Awk not working inside bash script

Im trying to write a bash script and trying to take input from user and executing a kill command to stop a specific tomcat.
...
read user_input
if [ "$user_input" = "2" ]
then
ps -ef | grep "search-tomcat" |awk {'"'"'print $2'"'"'}| xargs kill -9
echo "Search Tomcat Shut Down"
fi
...
I have confirmed that the line
ps -ef | grep "search-tomcat"
works fine in script but:
ps -ef | grep "search-tomcat" |awk {'"'"'print $2'"'"'}
doesnt yield any results in script, but gives desired output in terminal, so there has to be some problem with awk command
xargs can be tricky - Try:
kill -9 $(ps -ef | awk '/search-tomcat/ {print $2}')
If you prefer using xargs then check man page for options for your target OS (i.e. xargs -n.)
Also noting that 'kill -9' is a non-graceful process exit mechanism (i.e. possible file corruption, other strangeness) so I suggest only using as a last resort...
:)

Getting pids from ps -ef |grep keyword

I want to use ps -ef | grep "keyword" to determine the pid of a daemon process (there is a unique string in output of ps -ef in it).
I can kill the process with pkill keyword is there any command that returns the pid instead of killing it? (pidof or pgrep doesnt work)
You can use pgrep as long as you include the -f options. That makes pgrep match keywords in the whole command (including arguments) instead of just the process name.
pgrep -f keyword
From the man page:
-f The pattern is normally only matched against the process name. When -f is set, the full command line is used.
If you really want to avoid pgrep, try:
ps -ef | awk '/[k]eyword/{print $2}'
Note the [] around the first letter of the keyword. That's a useful trick to avoid matching the awk command itself.
Try
ps -ef | grep "KEYWORD" | awk '{print $2}'
That command should give you the PID of the processes with KEYWORD in them. In this instance, awk is returning what is in the 2nd column from the output.
ps -ef | grep KEYWORD | grep -v grep | awk '{print $2}'
This is available on linux: pidof keyword
I use
ps -C "keyword" -o pid=
This command should give you a PID number.
To kill a process by a specific keyword you could create an alias in ~/.bashrc (linux) or ~/.bash_profile (mac).
alias killps="kill -9 `ps -ef | grep '[k]eyword' | awk '{print $2}'`"

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