I'm using flutter_reactive_ble 5.0.2
I wonder is there a queue that make sure that only 1 command execute at a time or should I take care of it in my development?
If for example I call:
subscribeToCharacteristic
then without waiting call to write command that will cause the notification to raise, should I count on the fact that the notification will be finished before the write command (due to a command queue )
Related
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.
Is it possible to subscribe to an event in powershell when a particular executable is run?
We have an application that hogs up memory and then causes the system to crash, and if I could attach an event that starts a timer when it starts running and just kills after a certain amount of time, that would fix the issue.
You can use task scheduler to trigger on an Windows Event.Task Scheduler Trigger
Then you can add your powershell script as an action. Even delay the task if you like
As Crusadin sugggests, have a script run when an eventlog entry is made. I have just done the same thing here in work.
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
How do I run extra commands when a program in supervisor starts/restarts?
Particularly, In this case, I need to do a chmod on a file that the running process creates (socket file).
Actually, you can use the Event Listener. Supervisor provides a way for a specially written program (which it runs as a subprocess) called an “event listener” to subscribe to “event notifications”. When you receive the specific event, you can do whatever you want to do.
In you condition, you can listen the event which indicates that YOU_PROGRAM has been started/stopped, and then call the command to chmod the file.
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.