get-leader-pid

#!/bin/bash

CONT=$1
C=$(docker ps | grep $CONT | awk '{print $1}')
# "block" until the container shows up, yikes
while [ -z "$C" ]; do
    C=$(docker ps | grep $CONT | awk '{print $1}')
    sleep .5
done
NS_PID=$(ps aux | grep $C | grep -v grep | awk '{print $2}' | xargs ps -o pid --no-headers --ppid | head -n 1)
echo $NS_PID