Initial version of script working on bash, dash, zsh, and ksh.

all.sh

@@ -0,0 +1,54 @@
+#!/bin/sh
+set -e
+
+# From https://stackoverflow.com/a/360275
+kill_child_jobs() {
+    echo "In kill_child_jobs()..."
+    # Workaround for https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=482999
+    tmp="$(mktemp)"
+    jobs -p > "$tmp"
+    child_pids=$(cat "$tmp")
+    for child in $child_pids
+    do
+        # From https://unix.stackexchange.com/a/574169
+        if [ -n "${child##*[!0-9]*}" ]
+        then
+            echo Killing "$child"
+            # From https://stackoverflow.com/a/11231970
+            kill "$child" || true
+        fi
+    done
+
+    # zsh version from https://stackoverflow.com/a/36354483
+    # zsh doesn't have jobs -p
+    jobs > "$tmp"
+    cat "$tmp"
+    <"$tmp" sed --regexp-extended --quiet 's/\[([[:digit:]]+)\].*running.*/%\1/gp' | while read -r child
+    do
+        echo Killing job "$child"
+        kill "$child" || true
+    done
+
+    rm "$tmp"
+}
+cleanup() {
+    kill_child_jobs
+}
+
+#trap "kill_child_jobs" INT TERM QUIT
+#trap date INT TERM QUIT
+
+# From https://unix.stackexchange.com/a/240736
+for sig in INT QUIT HUP TERM ALRM USR1; do
+  trap "
+    cleanup
+    trap - $sig EXIT
+    kill -s $sig "'"$$"' "$sig"
+done
+trap cleanup EXIT
+
+yes aa &
+yes b &
+sleep 100 &
+
+wait