I'm working with an embedded computer that has a Debian on it. I already manage to run a command just before it has booted and play the "bell" to tell that is ready to work, and for example try to connect to a service.
The problem is that I need to play the bell (or run any command/program) when the system is halted so is safe to un-plug the power. Is there any runscript that run just after halt?
If you have a look in /etc/init.d, you'll see a script called halt. I'm pretty certain that when /sbin/halt is called in a runlevel other than 0 or 6, it calls /sbin/shutdown, which runs this script (unless called with an -n flag). So maybe you could add your own hook into that script? Obviously, it would be before the final halt was called, but nothing runs after that, so maybe that's ok.
Another option would be to use the fact that all running processes get sent a SIGTERM followed (a second or so later) by a SIGKILL. So you could write a simple daemon that just sat there until given a SIGTERM, at which point it went "ping" and died.
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I try to build a little REST service with Julia and Genie library. The last command is up(8888).
When I start this from Julia REPL all is ok.
When I start it from command line like >julia myrestapi.jl the program starts and stops immediately, i.e. up() doesn't go into an infinite loop.
What can I do to keep the server running?
When the Genie server is initiated in asynchronous mode, it runs off the main Task, and allows script processing to continue. If the script ends, the whole process and its spawned Tasks are stopped. This behavior is not good for a running web-service. To keep this from happening, two suggestions are:
Don't run the server off the main Task, by running synchronously. In code:
Genie.config.run_as_server = true
...
Genie.Server.up()
Make sure the main process does not end until the server Task ends. In code:
Base.JLOptions().isinteractive == 0 && wait()
The isinteractive condition, runs the wait() only when it is running as a script, as the usual desire when a REPL is present in interactive session, is to issue more commands, and the REPL keeps the server Task running in the background.
I'm using VS Code to write and debug a C++ program binding to libfuse.
Unfortunately, if you kill a libfuse process with SIGKILL, you then have to use sudo umount -f <mountpoint> before you can start the program again. It's a minor nuisance if I have to do this every time I want to stop or restart debugging, especially as I shouldn't have to authenticate to do such a regular task (the sudo is somehow necessary despite the mount occurring as my user).
While I think this is mainly FUSE's fault (it should gracefully recover from a process being ungracefully killed and unmount automatically instead of leaving the directory saying Transport endpoint is not connected), I also think there should be a way to customise VS Code (or any IDE) to run some clean-up when you want to stop debugging.
I've found that entering -exec signal SIGTERM in the Debug Console will gracefully unmount the directory correctly, stop the process and tell VS Code it's no longer debugging (status bar changes back from orange to blue). But I can't seem to find a way to automate this. I've tried using a .gdbinit file, with some inspiration from this question:
handle SIGTERM nostop
# This doesn't work as hook-quit isn't run when quitting via MI mode, which VS Code uses...
define hook-quit
signal SIGTERM
end
But as noted in the linked question, GDB ignores quit hooks when in MI mode, and VS Code uses MI mode.
The ideal solution for me would be if I could put something in a .vscode configuration file telling it to send -exec signal SIGTERM when I click the stop or restart buttons (and then wait for whatever notification it's getting that debugging has stopped, before restarting if applicable) but I imagine there probably isn't an option for that.
Even if the buttons can't be customised, I'd be happy with the ability to have a keybinding that would just send -exec signal SIGTERM to the Debug Console without me having to open said console and enter the command, though the Command Palette doesn't show anything useful here (nothing that looks like it will send a specified Debug Console command), so I don't expect there's a bindable command for that either.
Does anyone have any suggestions? Or would these belong as feature requests over on the VS Code github? Any way to get GDB to respect its quit hook in MI mode, or to get FUSE to gracefully handle its process being killed would be appreciated too.
I have a process in windows which i am running in startup. Now i need to make it if somehow that process get killed or stopped i need to restart it again in Windows 10?
Is there any way. Process is a HTTP server which if somehow stopped in windows i need to restart it. I have tried of writing a power-shell in which I'll check task-list status of process and then if not found I'll restart but that is not a good way. Please suggest some good way to do it.
I have a golang exe; under a particular scenario my process got killed or stopped i need to start it up again automatically. This has to be done imediately after the exe got killed. What is the best way to achieve this?
I will give you a brief rundown. You can enable Audit Process Termination in local group policy of the machine as shown below. In your case, success audits would be enough. Please note that the pic is for Windows 7. It may change with OS.
Now every time a process gets terminated, a success event will be generated and written to the security eventlog.
This will allow you to create a task scheduler that triggers on the generation of this event that calls a script that would run the process again. Simple right?
Well, you might have some trouble setting that task up especially when you want to pass details about the generating event to the script. This should help you get through that.
You can user Task scheduler for this purpose. There is a option of "restart on failure" which can be selected and whenever your process get failed it will restart again.
Reference :- https://social.technet.microsoft.com/Forums/windowsserver/en-US/4545361c-cc1f-4505-a0a1-c2dcc094109a/restarting-scheduled-task-that-has-failed?forum=winserverManagement
When trying to use Gatling CLI mode, the gatling starts successfully and recording is also happening. But the problem is when stopping the recording. As mentioned by the documentation (https://gatling.io/docs/2.3/http/recorder/), it can be stopped either by CTRL-C or by killing the pid available in .gatling-recorder-pid file.
I have used the second approach. Though the recording is stopped successfully, it is unable to create the simulation file. After doing some trial and error the only understanding i have now is that unless CTRL-C is pressed, it can never create a simulation file and killing pid only stops the recorder just before the file creation. But i am unable to simulate the CTRL-C action in windows command prompt from java. Please help. Thanks in advance
The kill command sends a SIGTERM (termination) signal. The SIGINT (interrupt) signal is the one equivalent to Ctrl+C.
kill -SIGINT processPIDHere
I have program that I need to run at startup in the background, so far I have it in rc.local like so:
sudo ./simple_program &
However this does not take into consideration if the program crashes. I need it so that whenever the program crashes, it is restarted again.
I think the approach is to write a bash script and run that instead in rc.local, where the bash script calls the simple_program and reruns it if needed. However, I'm not quite sure exactly what to do here. Could someone provide me a template?
Try with monit or daemontools, they are specifically designed to supervise other processes