Question

this is a better phrasing of what I intended in System.exit return code isn't detected by bash eval. I need a bash script that

1. runs an application (in my case it’s a java app)
2. directs stderr to a file
3. directs stderr + stdout to the terminal
4. returns the exit code of the app

for some reason, this is hard to do, even though it’s seems to me like a standard config for enterprise applications…
Thanks!

[EDIT]

testing solutions by wrapping this script:

#!/bin/sh
echo "This is Standard Out"
echo "This is Standard Error" >&2
cat meow

Answer 1

This will do your requirements :

#!/bin/bash

errlog="/var/log/my_app"

exec 2> >(tee "$errlog")

java -jar /path/to/app.jar

exit $?  

EXPLANATIONS

• exec 2 > catch STDERR (if you provide a file on the right, STDERR will be redirected in this file and no more on the terminal)
• >( ) is a bash process substitution (this create file descriptors in background)
• tee is there to both displays STDERR on the terminal & to save STDERR to the logfile