Re: wait for the next process to finish

[Wayne Davison <wayned@users.sourceforge.net>]

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On Mon, Dec 12, 2011 at 7:46 AM, Anthony R Fletcher <arif@mail.nih.gov>wrote:

> How can I wait for just the next job to finish?
>

One thing that may help you is TRAPCHLD.  Sadly, the signal handler doesn't
tell you what pid it is reacting to, nor the exit code.

TRAPCHLD() {
    echo here
    oldpids=($pids)
    pids=( )
    for p in $oldpids; do
        if kill -0 $p 2>/dev/null; then
            pids+=$p
        else
            #wait $p # Sadly, this doesn't work
            echo $p exited
        fi
    done
}
pids=( )
sleep 10 &
pids+=$!
sleep 20 &
pids+=$!
(sleep 15; false) &
pids+=$!
echo $pids
wait
echo done

It might be nice to set an environment parameter with the pid and status
info right before the dotrap(SIGCHLD) call in jobs.c.

..wayne..