jython script doesnt start when run in background - jython

I have a Jython script that is meant to run as a daemon in background, but somehow it doesn't start at all when I'm trying to run it in background.
So I've tried to do a most basic "hello world" script, it works fine if I execute it in console like
./mysqript.py
But same script executed like
./mysqript.py &
fails. It doesn't output error messages, it doesn't throw exceptions, it's actually not even quitting silently. It's just hanging forever in the process list as a zombie process doing nothing.
Why is that and how can I make it work?
PS: Environment is Jython2.7 beta.

Related

Sending the Valgrind to the background

I'v started a process with valgrind to find the leaks with the option --leak-check=full and redirecting the stdout and stderr outputs to a file. But the program seems to be running too long and now I want to send the process to the background so that I can close the terminal and check on the results at later time.
Here I've found that by using ctrl +z it will suspend the process and with bg and disown commands its possible to remove the process from the terminal and run on the background
But when I try that with valgrind the process doesnot respond to the ctrl + z command
Is there an alternative way to send the valgrind process to background? Or am I doing the whole thing wrong?

Can I retrieve the output of a program, that is running in another terminal and/or run by root as e.g a cronjob?

Just for the sake of the question, say I open a terminal an log into my Linux computer. I run a program that keeps outputting information on my screen, looping. I close the terminal window, and the program shuts down.
I set up a cronjob or a startup script that launches the same program as in example 1. The program is looping now, run as root.
I open a terminal, and log into my computer through SSH. Can I make a Bash script that retrieves the output of said program, even if it's running somewhere in the background? I mean, is the program "virtually" outputting information (as in example 1)?
The program closes stdout and stderr when it exits. Looping it as you describe will just cause it to start and exit continuously. You could look at redirecting stdout and stderr.

File.execute() is not executing my script. How to debug this issue?

I'm writing a script for Illustrator CS6 in ExtendScript. At the end of my script, I want to spawn a task (a second script, in Ruby) using File.execute(). However, it's not working. And I'm at a loss as how to debug the problem -- how can I figure out why this isn't working?
Here's the end of my ExtendScript file:
// Do a bunch of other work, then:
var rubyFile = new File(scriptFolder + 'BuildHtmlWalkthrough.rb');
alert(rubyFile.exists);
var result = rubyFile.execute();
alert(result);
Both rubyFile.exists and result are always true, indicating that the script launched OK. But the script does not appear to run, at all. I've tried the following diagnostics:
The Ruby script does successfully run from the command line. The script's permissions are -rwxr-xr-x
I added a call to system("touch /blah/blah/blah") as the very first line of the Ruby script. The file does not get touched.
I thought maybe the ExtendScript process was terminating before the Ruby script could run, so I added a long for loop after rubyFile.execute(). Spinning for > 30 seconds did not help.
What can I do to debug, or solve, this problem?
I'm on MacOS X v10.9.1. And for reference, this is the documentation for File.execute():
File.execute (): Boolean
Core JavaScript Classes
Executes or opens
this file using the appropriate application, as if it had been
double-clicked in a file browser. You can use this method to run
scripts, launch applications, and so on. Returns true immediately if
the application launch was successful.
It's probably doing the "opens this file using the appropriate application" instead of executing, and returns true because the file successfully opens (or is already open in its associated app). If I have a python script and do
f= new File("~/Documents/misc_scripts/getpixelrgb.py");
f.execute();
, it opens it in my script editor, even if the file's execute flags are set.
I'm on OSX, btw
In After Effects, there is system.callSystem() to execute command line commands, but I'm afraid that is absent in Illustrator (I'm assuming you're doing this for Illustrator because of the tag). Are you on OSX or Windows? There are ways around this, by making an executable .app (OSX) or .exe (Win) and calling that with execute(). If I were doing this, I'm on OSX and I'd make an AppleScript app that does 'do shell script' to make the ruby system call. On Windows, it's different. One solution you might like if you're on windows: ocra, which is ruby-specific (http://ocra.rubyforge.org/). It may be possible to run a .bat file on Windows that calls the ruby script, but I'm not sure.
[edit!]
Terribly sorry for the extraneous Windows info (for someone else, I guess). Just saw your note about being on OSX. So you might want to use the AppleScript solution.
[edit again]
So, if my ruby script ("test.rb") is:
#!/usr/bin/env ruby
print "Hello"
and my AppleScript is:
do shell script "cd /testing_folder/; ruby test.rb"
Then I get "Hello" returned in AppleScript, but ExtendScript will just return true.

Start program via ssh in Jenkins and using it in Jenkins build

Hello people.
I'm using Jenkins as CI server and I need to run some performance test using Jmeter. I've setup the plugin and configured my workspace and everything works ok, but I have to do some steps manually and I want a bit more of "automation".
Currently i have some small programs in a remote server. These programs make some specific validations, for instance (just to explain): validates e-mail addresses, phone numbers, etc.
So, before I run the build in jenkins, I have to manually start the program (file.sh) I want:
I have to use putty (or any othe ssh client) to conect to the server and then run, for instance, the command
./email_validation.sh
And the Jmeter test runs in a correct way, and when the test is done I have to manually "shut down" the program I started. But what I want is trying to start the program I need in Jenkins configuration (not manually outside Jenkins, but in "execute shell" or "execute remote shell using ssh" build step).
I have tried to start it, but it get stuck, because when Jenkins build finds the command
./email_validation.sh
the build stops, it waits for the command to finish and then it will continue the other build steps, but obviously, I need this step not to finish until the test is executed.
Is there a way to achieve this? Thanks
Run your command as a background process by adding the & symbol at the end of the command and use the nohup command in case the parent process gets a hangup signal, e.g.
nohup /path/to/email_validation.sh &
If the script produces any output, it will go by default to the file nohup.out in the current directory when the script was launched.
You can kill the process at the end of the build by running:
pkill email_validation.sh

executing NSTask in the background

I'm executing a shell script using NSTask but the problem is that the shell script is one of those scripts that keeps running until you press control+c. It starts up fine but then my mac application just waits for it to end. How can I make it so that it detaches the task from the mac application and goes and runs it in a background.
Don't call waitUntilExit or otherwise run the task synchronously. If the task has lots of output, make sure you read and process the data or else an i/o buffer will fill and it'll block.
In general, you shouldn't be using NSTask for a daemon like operation anyway. You should be using launchd.