brooklyn-docs/guide/yaml/example_yaml/vanilla-bash-netcat-more-commands.yaml

name: Netcat Example with Explicit Check and Stop Commands
location: localhost
services:
- type: org.apache.brooklyn.entity.software.base.VanillaSoftwareProcess
  name: Simple Netcat Server
  launch.command: |
    echo hello | nc -l 4321 &
    echo $! > $PID_FILE

  # The following overrides demonstrate the use of a custom shell environment as well as
  # check-running and stop commands. These are optional; default behavior will "do the
  # right thing" with the pid file automatically.

  env:                  { CHECK_MARKER: "checkRunning", STOP_MARKER: "stop" }
  checkRunning.command: echo $CHECK_MARKER >> DATE && test -f "$PID_FILE" && ps -p `cat $PID_FILE` >/dev/null
  stop.command:         echo $STOP_MARKER  >> DATE && test -f "$PID_FILE" && { kill -9 `cat $PID_FILE`; rm /tmp/vanilla.pid; }