psancestros

#!/bin/bash
#
#Description: Dado un PID válido muestra la lista de PIDs desde el dado hasta el PID 0
#
#Author:jMa
#

if [ \( $# -eq 1 \) ] && [ \( `ps aux | tr -s " " | cut -d " " -f 2 | grep $1 | wc -c` -gt 0 \) ]
then
  pid=$1
  echo -n "PID $1-->"
  if [ "$1" -eq "0" ]
  then
    echo
  fi
  while [ "$pid" != "0" ]
  do
    ppid=`ps -l $pid | tr -s " " | cut -d " " -f5 | tail -1`
    if [ "$ppid" != "0" ]
    then
      echo -n "$ppid-->"
    else
      echo  "$ppid"
    fi
    pid=$ppid
  done
else
  echo -e "Error\nSintax: ./psacestros PIDExistente"
fi