Jtdylktuy

So lately I've been trying to quit a running process in a clean manner, through its 'quit' command.
If I don't go through the entire quitting process it creates a .lck file and I don't want that.

I've been unable to succeed, I've tried multiple approaches such as echoing 'quit' and 15, 12, n to /proc/pid/fd/0, but none of these managed to validate what was in the buffer.
I've tried to screen a terminal, and reptyr the process into it so it goes into a terminal but doing so I can't find a way to emulate the enter key.

So, since it seems that no matter what I try I can't find how to validate a text buffer, I decided that I should use that built-in quit directly and not trying to input it.

Is there ways to use another process commands directly ? When I try

quit | reptyr <process pid> 

for instance, it says that quit isn't a recognized command, because the shell is trying to execute it in its own environment and I wish to execute it in the other process environment.

NOTE: Some info about said running process, I have to provide several input to quit it.

• 
  

  press Ctlr + C to stop it
  It then swap to SimDebug mode which just provides infos should I press enter a few times. It is in read mode looking like

  
  
  

  SimDebug>

  
  



• There I should write quit and press enter, then q and enter, n and enter then lastly enter.

I manage in my script to do the 1st point by using kill -INT and I'm stuck with the rest.

EDIT : I can skip some of those task using the SIGTERM as suggested, although it gets me to the last read

Do you want to do a checkpoint (Y/N)
_

And there I can't do another SIGTERM, a SIGKILL pops up an error message and a .lck file is created. I only do need to feed a "n" or "y" inside it.
I will take a look at the expect since now I have the question but i'm still wondering how to use it to be listening to the process and not the terminal in which i'm running the script.

Run the program in tmux (or run reptyr in tmux to "hijack" already running process, if you need; e.g. tmux new-session reptyr "$pid_to_hijack"). Then you can do this from another terminal:

pane='$0:@0.1'

tmux send-keys -t "$pane" C-c                # a way to send Ctrl+C

sleep 2                                      # let the program react (you may or may not need it)

tmux send-keys -t "$pane" Enter Enter Enter  # "should I press enter a few times"

tmux send-keys -t "$pane" quit Enter         # "I should write quit and press enter"

tmux send-keys -t "$pane" q Enter            # "then q and enter"

tmux send-keys -t "$pane" n Enter            # "n and enter"

tmux send-keys -t "$pane" Enter              # "then lastly enter"

where the example $0:@0.1 identifies the pane in which your program runs (you must single-quote this string, otherwise the shell will expand $0). If you name your tmux session(s) and window(s), then this string may be like mysession:mywindow.0.

As I understand you're trying to send command to a "subshell". Let's say something like running command quit() in a python shell? Or any other programs that waits for an input?

If it's that what you want, I think you're looking for something like :

$> python <<< "quit() python <<< "<many instructions here>" python <

$> file_containing_instructions.py #with quit() at the end python << END

$> <instructions> <on_many_lines> END

Now if you're trying to keep a reference to a running process and then sent instructions to it later, then the only thing I can tell you at the very moment is coproc. You can learn a bit about it with help coproc, there is more in man bash and even more in info bash.

Good luck

EDIT: Just came back on that tab and saw the crapy formating so I fixed it. Also, I wanted to add that I haven't been able to make it work with Python but most likely it's doable, althogh with other shell like bash it works like that.

$> coproc PRC { bash; } &

$> echo 'echo $PATH' >&${PRC[1]}

$> read -t1 -u ${PRC[0]} resp

$> echo $resp

/the/PATH/is/printed

$> echo 'exit' >&${PRC[1]}

$> jobs

[1]+ Done