Major Description
I downloaded zookeeper 3.5.6 and was unable to start because the zookeeper_server.pid file was not being created.
The problem was in the line ZOO_DATADIR="$(echo -e "${ZOO_DATADIR}" | sed -e 's/^[[:space:]]//' -e 's/[[:space:]]$//')"
After removing -e option from the echo command, it started successfully.
