app uses signals helper

app/signals.sh

@@ -0,0 +1,25 @@
+signals_trap_with_arg() {
+    func="$1" ; shift
+    for sig ; do
+        echo "$func $sig"
+        trap "$func $sig" "$sig"
+    done
+}
+
+signals_wait_forever() {
+    while true
+    do
+        tail -f /dev/null & wait ${!}
+    done
+}
+
+signal_name_to_number() {
+    SIGNAME="$1"
+    trap -l | sed -nr "s/.*\b([0-9]+)\) $SIGNAME.*/\1/p"
+}
+
+signal_return_val() {
+    SIGNAME="$1"
+    SIGNUM=$(signal_name_to_number ${SIGNAME})
+    echo "128 + $SIGNUM" | bc
+}