I'm writing a simple menu using the dialog utility in a bash script.
The idea is that the menu script will run in a screen session which I can connect to over SSH (or whatever else).
I want to then use the menu to start/stop applications running on the machine. For example there might be a menu item called "Start/Stop gEdit". When it's selected, one of two things could happen:
If gEdit is not currently running, it starts it
If gEdit is currently running, it stops it
My question is, what is the best way to launch (and close) applications from my bash script? This is on Debian.
Edit: Is upstart the right choice here? It seems weird to write an upstart script for something like gEdit.
AFAIK..
You can run/stop applications from bash script the same way you do it from command line.
./ to run
kill -9 pid to close.
Debian now is using systemd Not upstart.
If you want to see if gedit is running in order to start/stop you can do something like pgrep gedit:
if [ pgrep gedit > 0 ]
echo "Something"
then
echo "Other thing"
Related
I have a couple cli-based scripts that run for some time.
I'd like another script to 'restart' those other scripts.
I've checked SO for answers, but the scenarios were not applicable enough to mine, as I'm trying to end Terminal processes using Terminal.
Process:
2 cli-based scripts are running (node, python, etc).
3rd script is run and decides whether or not to restart the other 2.
This can't quit Terminal, but has to end current processes.
3rd script then runs an executable that restarts everything.
Currently none of the terminal windows are named, and from reading the other posts, I can see that it may be helpful to do so.
I can mostly set this up, I just could not find a command that would end all other terminal processes and close them.
There are a couple of ways to do this. Most common is having a pidfile.
This file contains the process ID (pid) of the job you want to kill
later on. A simple way to create the pidfile is:
$ node server &
$ echo $! > /tmp/node.pidfile
$! contains the pid of the process that was most recently backgrounded.
Then later on, you kill it like so:
$ kill `cat /tmp/node.pidfile`
You would do similar for the python script.
The other less robust way is to do a killall for each process and assume you are not running similar node or python jobs.
Refer to
What is a .pid file and what does it contain? if you're not familiar with this.
The question headline is quite general, so is my reply
killall bash
or generically
killall processName
eg. killall chrome
I'm trying to write a Shell script (for use in Mac OSX Termninal) that will run a command to start a development server (gulp serve). I have it working except the server is continuously running so it doesn't allow me to enter subsequent commands in the same window without stopping the server (Control+C). My question is, is there a way I can run the process in the background and/or suppress any/all output? My goal is to also write a 'stop server' command that will kill the process (which I'm also unsure how to do). I've tried all combinations of using ampersands and &>/dev/null and nothing quite works. Here's what I have so far:
if [ "$1" = "server" ]
then
if [ "$2" = "on" ]
then
cd / & gulp serve --gulpfile /server/example/gulpfile.js # the output is still shown
printf "\033[0;32mserver is online.\033[0m\n"
else
killall tail &>/dev/null 2>&1 # this doesn't kill the process
printf "\033[0;32mportals is offline.\033[0m\n"
fi
fi
You're doing the output redirection on killall, not gulp, so gulp will continue to merrily split out text to your terminal. Try instead:
cd / && gulp server --gulpfile /server/example/gulpfile.js >/dev/null 2>&1 &
Secondly, your kill command doesn't kill your process because you're not telling it to; you're asking it to kill all tail processes. You want instead:
killall gulp
These modifications should be the most direct path to your goal. However, there are a few additional things that may be useful to know.
Process management has a long history in the *nix world, and so we've been inventing tools to make this easier for a long time. You can go through re-inventing them yourself (the next step would be to store the PID of your gulp process so that you can ensure you only kill it and not anything else with "gulp" in the name), or you can go all the way and write a system monitoring file. For Linux, this would be SysV, Upstart, or systemd; I'm not sure what the OS X equivalent is.
However, since you're just doing this for development purposes, not a production website, you probably don't actually need that; your actual goal is to be able to execute ad-hoc shell commands while gulp is running. You can use terminal tabs to do this, or more elegantly use the splitting capabilities of iTerm, screen, or tmux. Tmux in particular is a useful tool for when you find yourself working a lot in a terminal, and would be a useful thing to become familiar with.
First, to run the process in the background
cd / && gulp serve --gulpfile /server/example/gulpfile.js > /tmp/gulp.log &
after cd you need && (and) and & to run in the background at the end.
To kill all gulp processes
killall gulp
A script that keeps updating the log file. data like system time and date, users currently logged in etc for every interval of time say 5 minutes. THE SCRIPT MUST RUN EVEN AFTER THE TERMINAL HAS BEEN CLOSED.
Actually, no.
First of, you don't need sh:
$ ./newscript.sh &
This is enough. This will start a background process. But your terminal is still controlling it. To achieve the behavior you want, do this:
$ disown %1
This will disown the job with the jobspec 1 (which is like an id), which was the one you started beforehand. Now you can close the terminal.
Hurrah!! I would like to answer my question since i have got the solution.
For example, I'm running a script newscript.sh I want to run this in background and continue someother job in the terminal or i can close the terminal.
[yourname # username ~]$ sh newscript.sh &
and hit enter. You will get a PID and your job will be attached to the background.
To kill the same process, use the PID
For eg.,
kill 1205212
Thank you.
I have a VM that I want running indefinitely. The server is always running but I want the script to keep running after I log out. How would I go about doing so? Creating a cron job?
In general the following steps are sufficient to convince most Unix shells that the process you're launching should not depend on the continued existence of the shell:
run the command under nohup
run the command in the background
redirect all file descriptors that normally point to the terminal to other locations
So, if you want to run command-name, you should do it like so:
nohup command-name >/dev/null 2>/dev/null </dev/null &
This tells the process that will execute command-name to send all stdout and stderr to nowhere (instead of to your terminal) and also to read stdin from nowhere (instead of from your terminal). Of course if you actually have locations to write to/read from, you can certainly use those instead -- anything except the terminal is fine:
nohup command-name >outputFile 2>errorFile <inputFile &
See also the answer in Petur's comment, which discusses this issue a fair bit.
Well, what I need to do actually is CTRL-Z out of a process that got started from insert mode in GVim.
My command :Cdprun executes cdprun.sh which runs a sudo-ed daemon. I can add & at the end of the sudo-ed daemon call to run in the background and that works but the user doesn't get prompted for a password. Instead I want to just CTRL-Z out of it but the keyboard interrupt doesn't work. Any ideas? Thx.
You generally have two options in this case: generic is using something like vim-addon-async mentioned by #Nicalas Martin or vim with built-in interpreters support: tcl with expect module, python with pyexpect, perl with Expect, maybe something else (note: all of the mentioned packages are not shipped with tcl/python/perl). Second is specific to current situation: it is backgrounding in the other place. From your explanation I guessed that you have a script looking like
#!/bin/sh
<...>
sudo run-daemon --daemon-args # Last executed line
, am I right? Than you can just put backgrounding in another place: not
sudo run-daemon --daemon-args &
, but
sudo sh -c "nohup run-daemon --daemon-args &"
Here is a script to deal with asynchronous command in vim. Not a perfect solution but could be a good temporary solution. http://www.vim.org/scripts/script.php?script_id=3307