Run multiple commands in parallel, and return whenever one of them fails or all of them succeed

This code gives the right exit code, and kills the survivor process:

#/bin/bash

# trap for SIGTERM and set RET_VALUE to false
trap "RET_VAL=false" SIGTERM

MY_PID=$$
# Initialize RET_VALUE to true
RET_VAL=true

# This function will executed be in a separate job (see below)
thread_listener() {
    # Starts the long time job 
    ./longJob.sh &
    PID=$!
    # trap for sigterm and kill the long time process
    trap "kill $PID" SIGTERM
    echo waiting for $PID
    echo Parent $MY_PID
    # Send a SIGTERM to parent job in case of failure
    wait $PID || kill $MY_PID
    exit
}

echo $MY_PID

# Runs thread listener in a separate job
thread_listener &
PID1=$!

# Runs thread listener in a separate job
thread_listener &
PID2=$!

wait
# send sigterm to PID1 and PID2 if present
kill $PID1 2> /dev/null
kill $PID2 2> /dev/null
# returns RET_VALUE
$RET_VAL

See the comments for an explanation of the code. The trick is to starts jobs able to accept or send signal to parent job if needed.

The child job send a signal to the parent in case of a failure of its long time job and the parent send a signal to its childs after the wait (it the parent receive a signal the wait returns immediatly)

The recent versions of GNU Parallel have focused on exactly that problem. Kill running children, if a single one fails:

parallel --halt now,fail=1 'echo {};{}' ::: true false true true false

Kill running children, if a single one succeeds:

parallel --halt now,success=1 'echo {};{}' ::: true false true true false

Kill running children, if 20% fails:

parallel -j1 --halt now,fail=20% 'echo {#} {};{}' ::: true true true false true true false true false true

Kill the child with signals TERM,TERM,TERM,KILL while waiting 50 ms between each signal:

parallel --termseq TERM,50,TERM,50,TERM,50,KILL -u --halt now,fail=1 'trap "echo TERM" SIGTERM; sleep 1;echo {};{}' ::: true false true true false

Solved a similar situation, share here if ever it helps to someone.

I have got three commands to run.

• server1 and server2 are long running commands, e.g. webservers.
• healthcheck command runs some checks to make sure that the servers are okay. It requires the two servers up to perform the tests.

Required behavior:

• If healthcheck is successful (return code is 0), block until the servers are running. This is normal operation.
• If healthcheck fails, return immediately. This is wanted if there is a problem with servers.

The following does the job for me:

server1 & server2 & healthcheck && wait