How to check whether a background job is alive? (bash)

background, bash, jobs, process, shell

Solution

You can get the PID of the most recent background job with `$!`. You could then check the exit status of ps to determine if that particular PID is still in the process list. For example:

sleep 30 &
if ps -p $! >&-; then
    wait $!
else
    jobs
fi

Problem

I have the following bash script, we can call it `script1.sh`: ``` #!/bin/bash exec ./script2.sh & sleep 5 if job1 is alive then #<--- this line is pseudo-code! exec ./script3.sh & wait fi ``` As can be seen, the script executes `script2.sh` as a background job and then waits 5 seconds (so `script2.sh` can do some initialization stuff). If the initialization succeeds, the `script2.sh` job will still be alive, in which case I also want to start `script3.sh` concurrently; if not, I just want to quit. However, I do not know how to check whether the first job is alive, hence the line of pseudo-code. So, what should go in its place?

Original source