I am running my application from the custom shell. we have set DefaultReturnCodeAction to Restart shell.
If there any way to run script when shell exits instead of restart shell.
Related
I've been writing Bash scripts that work with a database lately.
To access the database, I need to ssh into a DiskStation (requires password) and then sudo a docker command (requires password) to access the container that the database is in. Only then can I execute and test out my scripts.
I wrote an expect script that automates this process and I want to embed it in my Bash scripts, but the only problem is the shell closes as soon as the expect script finishes executing.
Does anybody know how to work around this? I attached a photo with specific info removed. Bash script with embedded expect script
How to mark a configured shell script to executed command in Azure VM Custom Script Extension ?
It is running the shell commands in configured CSE but it has not ending up the script due to one of my command. My command will be running a small HTTP listener kind of server.
If make "exit 0" will mark CSE as command executed and so it will exits in my powershell script where i encountered this CSE.
If my understanding is right. You could run HTTP listener in the background and exit your script. Just use below:
nohup <bash shell> &
man nohup
nohup - run a command immune to hangups, with output to a non-tty
& to the command line to run in the background:
I know that execute a command and add & to the end would create a job and make the command execute in background.
Now I want to create a job in a bash shell. I tried
#!/bin/bash
my-job &
# some other tasks
Then I executed jobs, but I got no output. However, ps aux does show my-job is running in the background.
I want to create a job inside a script, because in some cases I want to bring the job into foreground.
jobs are usually an interactive shell concept, as there is usually a controlling terminal involved.
A shell script is executed in a non-interactive, non-login session of shell, hence no job control by default.
You can force job control inside a script, by setting:
set -m
inside the script.
From help set:
-m Job control is enabled.
Running a bash script in the background with job control enabled and stdin closed will exit the PARENT shell. How can that happen?
To demonstrate make this background_bash_script:
#!/bin/bash
set -m
ruby -e "puts :here"
Then run it in bash - it will exit the shell you ran it in. The ruby command does not matter although it appears it must be a command and not a bash built-in (for example awk --version works but true does not). To get a better look I've been running it in yet another instance of bash. A full session looks like this.
parent: PS1='child: ' bash
child: ./background_bash_script <&- &
[1] 3893
child: here
exit
parent:
Confusing!
What seems like is happening is that after set -m is run in the script, the next command that is run is forced to be in the foreground process group, which takes the original shell out of the foreground process group. Once that process exits, the shell running the script is now in the foreground process group, but once that shell exits, the original shell doesn't put itself back into the foreground process group because it ran the script in the background. So you now have an interactive shell that is in a background process group.
You can see some weird behavior here if you put a sleep at the end of your script so that it doesn't exit immediately. When you run the script in the background you get the terminal prompt back, but now your interactive shell isn't in the foreground process group! As soon as you try to type anything the shell exits. I'm not sure exactly what mechanism causes the exit. Since the shell is in the background, any attempts to read or write characters to the terminal should result in SIGTTIN OR SIGTTOU, but these signals don't cause the shell to exit in my tests.
I am writing my first ever bash script, so excuse the noobie-ness.
It's called hello.bash, and this is what it contains:
#!/bin/bash
echo Hello World
I did
chmod 700 hello.bash
to give myself permissions to execute.
Now, when I type
exec hello.bash
My putty terminal instantly shuts down. What am I doing wrong?
From the man page for exec:
If command is supplied, it replaces the shell without creating a new process. If no command is specified, redirections may be used to affect the current shell environment.
So your script process runs in place of your terminal and when it exits, so does your terminal. Just execute it instead:
./hello.bash