assgn3/process-pid.sh

   1 #!/usr/bin/env bash
   2
   3 USAGE="usage: $0 <pid> [-h, -a] [-f, -e] [-s <regexp>]"
   4 OPTIND=2
   5
   6 if [[ ! "$1" =~ ^-?[0-9]+$ ]]; then
   7         echo $USAGE; exit 1
   8
   9 elif [[ ! -d /proc/$1 ]]; then
  10         echo "invalid pid '$1'"; exit 1
  11 fi
  12
  13 echo -e "pid '${1}' refers to a running process.\n"
  14
  15 while getopts ":s:hafe" opts; do
  16         case "${opts}" in
  17                 s)
  18                   cat /proc/"$1"/status | grep "$OPTARG"
  19                   ;;
  20                 h)
  21                   echo "$USAGE"; DROPBOOL=1
  22                   ;;
  23                 a)
  24                   echo "written by ian sutton."; if [[ $DROPBOOL ]]; then exit 0; fi
  25                   ;;
  26                 f)
  27                   ls /proc/"$1"
  28                   ;;
  29                 e)
  30                   if [[ ! `readlink /proc/$1/exe` ]]; then
  31                         echo "no permissions to read pid '$1's executable path"; exit 1
  32                   fi
  33
  34                   echo -n "executable path of pid '$1': "
  35                   readlink /proc/"$1"/exe
  36                   ;;
  37                 \?)
  38                   echo "bad option \"-$OPTARG\""; exit 1
  39                   ;;
  40                 :)
  41                   echo $USAGE; exit 1
  42                   ;;
  43         esac
  44         echo -ne "\n"
  45 done
  46
  47 # -h case
  48 #if [[ "$1" -eq "-h" ]]; then
  49 #       echo "$USAGE"; exit 0
  50 #
  51 # <pid> case
  52 #elif [[ "$1" =~ ^-?[0-9]+$ ]]; then
  53 #       if `ps $1 > /dev/null 2>&1`; then
  54 #               echo "you win!"; exit 0
  55 #
  56 #       else
  57 #               echo -ne "invalid pid\n$USAGE"; exit 1
  58 #       fi
  59 #
  60 # -e <pid> case
  61 #elif [[ "$1" -eq "-e" && "$2" =~ ^-?[0-9]+$ ]]; then
  62 #       if `ps $2 > /dev/null 2>&1`; then
  63 #               echo "you win!"; exit 0;
  64 #
  65 #       else
  66 #               echo -ne "invalid pid\n$USAGE"; exit 1
  67 #
  68 # -s <pid> <regex> case
  69 #elif [[ "$1" -eq "-s" && "$2" =~ ^-?[0-9]+$ ]]; then
  70 #       if `ps $2 > /dev/null 2>&1`; then
  71 #               echo "you win!"; exit 0;
  72 #
  73 #       else
  74 #               echo -ne "invalid pid\n$USAGE"; exit 1
  75 #
  76 #else
  77 #       echo "$USAGE"; exit 1
  78 #fi