I am facing a weird problem. Every time I call a particular command cmd via subprocess.Popen(cmd).wait(), the stty gets bad (does not echo my further commands on the shell, newline does not work, etc.) when the command is over. I have to run stty sane to get the stty fine again. What could be the reason for this?
Update The command I am running is starting the elasticsearch process. The command launches the process in the background.
It's possible that the command you're running is emitting some escape sequences into your terminal that are changing its mode or other settings. Programs that need the full terminal capability do that (e.g. text based editors).
Capturing the standard output of the program you're executing and preventing it from going to the screen might help. Have you tried that?
Related
I've created an app that runs on cygwin, that will open some new shells and run python script on each of them. The problem started when I wanted to have control on the new shells and kill them at will. after a lot of digging I decided to use the following command:
subprocess.run('mintty.exe -t {} -h always -e {} &'.format(app_name, run_app_cmd), shell = True)
and later when I'll want to kill it use:
subprocess.run('kill -2 {}'.format(apps[app].shell_pid), shell = True).
it worked pretty well until I realized that A-L-O-T of times the new terminal gets stuck and doesn't respond, and I don't like it. I made some more digging and I found that while I thought that the python on the current mintty executes the command and opens the new terminal, what that actually happens is that the windows host opens the new mintty (the PPID of the new terminal is 1), and then probably the signal goes through some windows problems and etc.
the reason that I want each of the scripts in a separate terminal is that each of them have a lot of output, and I want them in different windows.
Now, after all this explanation, is there any way to prevent this? I don't want these stuck to become a part of my life...
What I would like to do is launch an interactive ipython session from notepad++, and keep the window open (in interactive mode) after a script completes, but for the window to close once I exit from ipython. This seems like a fairly simple task, but I'm having trouble finding the answer.
In notepad++, I have entered the following for the Run command (F5):
cmd /k ipython -i "$(FULL_CURRENT_PATH)"
This works fine: it opens and runs the script I am editing using ipython, and keeps the ipython session open once the script is complete.
However, after entering the exit command, I have to enter exit a second time at the command prompt) to close the window (or close it with the mouse). It would be nice if I didn't have to enter exit twice. Is there a solution to get things working the way I want them to work?
I have tried removing /k flag (my understanding is this flag keeps the window open):
cmd ipython -i "$(FULL_CURRENT_PATH)"
However, the script does not seem to run at all in this case.
Well I discovered the answer just before I was about to post the question! Instead of deleting it altogether, I thought I would go ahead and post the resolution so that others can find it later. It turned out to be pretty simple!:
ipython -i "$(FULL_CURRENT_PATH)"
(Note that in order for this to work, ipython must be available as a program to be run from a command prompt.)
I would like to create a simple Python program that will concurrently execute 2 independent scripts. For now, the two scripts just print a sequence of numbers but my intention is to use this program to concurrently run a few Twitter streaming programs in the future.
I suspect I need to use subprocess.Popen but I cannot quite get my head around what arguments I should put in there. There was a similar question on StackOverflow but the code provided there (pasted below) doesn't print anything. I will appreciate your help.
My files are:
thread1.py
thread2.py
import subprocess
subprocess.Popen(['screen', './thread1.py']))
subprocess.Popen(['screen', './thread2.py'])
Use supervisord
supervisord is process control system just for the purpose of running multiple command line scripts.
It features:
multiple controlled processes
autorestarting failed runs
log stdout and stderr output
starting scripts in order (using priority)
command line utility to view latest log output, stop, start, restart the processes
This solution works only on *nix based systems, it is not available on Windows.
As wanderlust mentioned, why do you want to do it this way and not via linux command line?
Otherwise, the solution you post is doing what it is meant to, i.e, you are doing this at the command line:
screen ./thread1.py
screen ./thread2.py
This will open a screen session and run the program and output within this screen session, such that you will not see the output on your terminal directly. To trouble shoot your output, just execute the scripts without the screen call:
import subprocess
subprocess.Popen(['./thread1.py'])
subprocess.Popen(['./thread2.py'])
Content of thread1.py:
#!/usr/bin/env python
def countToTen():
for i in range(10):
print i
countToTen()
Content of thread2.py:
#!/usr/bin/env python
def countToHundreds():
for i in range(10):
print i*100
countToHundreds()
Then don't forget to do this on the command line:
chmod u+x thread*.py
You can also just open several Command Prompt windows to run several Python programs at once - just run one in each of them:
In each Command Prompt window, go to the correct directory (such as C:/Python27) and then type 'python YourCodeNo1.py' in one Command Prompt window, 'python YourCodeNo2.py' in the next one ect. .
I'm currently running 3 codes at one time in this way, without slowing any of them down.
I am a newbie in Fabric, and want to run one command in a background, it is written in shell script, and I have to run that command via Fabric, so lets assume I have a command in shell script as:
#!/bin/bash/
java &
Consider this is a file named myfile.sh
Now in Fabric I am using this code to run my script as:
put('myfile.sh', '/root/temp/')
sudo('sh /root/temp/myfile.sh')
Now this should start the Java process in background but when I login to the Machine and see the jobs using jobs command, nothing is outputted.
Where is the problem please shed some light.
Use it with
run('nohup PATH_TO_JMETER/Jmetercommand & sleep 5; exit 0)
maybe the process exists before you return. when you type in java, normally it shows up help message and exits. Try a sleep statement or something that lingers. and if you want to run it in the background, you could also append & to the sudo call
I use run("screen -d -m sh /root/temp/myfile.sh",pty=False). This starts a new screen session in detached mode, which will continue running after the connection is lost. I use the pty=False option because I found that when connecting to several hosts, the process would not be started in all of them without this option.
I'm wanting to open a terminal from a Python script (not one marked as executable, but actually doing python3 myscript.py to run it), have the terminal run commands, and then keep the terminal open and let the user type commands into it.
EDIT (as suggested): I am primarily needing this for Linux (I'm using Xubuntu, Ubuntu and stuff like that). It would be really nice to know Windows 7/8 and Mac methods, too, since I'd like a cross-platform solution in the long-run. Input for any system would be appreciated, however.
Just so people know some useful stuff pertaining to this, here's some code that may be difficult to come up with without some research. This doesn't allow user-input, but it does keep the window open. The code is specifically for Linux:
import subprocess, shlex;
myFilePathString="/home/asdf asdf/file.py";
params=shlex.split('x-terminal-emulator -e bash -c "python3 \''+myFilePathString+'\'; echo \'(Press any key to exit the terminal emulator.)\'; read -n 1 -s"');
subprocess.call(params);
To open it with the Python interpreter running afterward, which is about as good, if not better than what I'm looking for, try this:
import subprocess, shlex;
myFilePathString="/home/asdf asdf/file.py";
params=shlex.split('x-terminal-emulator -e bash -c "python3 -i \''+myFilePathString+'\'"');
subprocess.call(params);
I say these examples may take some time to come up with because passing parameters to bash, which is being opened within another command can be problematic without taking a few steps. Plus, you need to know to use to quotes in the right places, or else, for example, if there's a space in your file path, then you'll have problems and might not know why.
EDIT: For clarity (and part of the answer), I found out that there's a standard way to do this in Windows:
cmd /K [whatever your commands are]
So, if you don't know what I mean try that and see what happens. Here's the URL where I found the information: http://ss64.com/nt/cmd.html