Shell Programming and Scripting

#/bin/sh
_key()
{
  local kp
  ESC=$'\e'
  _KEY=
  read -d '' -sn1 _KEY
  case $_KEY in
    "$ESC")
        while read -d '' -sn1 -t1 kp
        do
          _KEY=$_KEY$kp
          case $kp in
            [a-zA-NP-Z~]) break;;
          esac
        done
    ;;
  esac
  printf -v "${1:-_KEY}" "%s" "$_KEY"
}

_key x

case $x in
  $'\e[15~') echo You have pressed F5 ;;
esac

#/bin/sh
countdown=10
while [[ ${countdown} -ge 0 ]]
do
    #echo ${countdown}
    echo "${countdown} second(s) left"
    sleep 1
    countdown=$(( ${countdown} - 1 ))
done

countdown=10
while [[ ${countdown} -ge 0 ]]
do
    
    echo "Automatic search using today's date will begin in ${countdown} second(s)." 
    echo "Press F5 to cancel and specify another date."
    sleep 1
    countdown=$(( ${countdown} - 1 ))
    
    if [[ $countdown == 0 ]]; then
        # run the automatic search using today's date
        # by calling the SearchAuto function
        SearchAuto
        fi
        
#more script needed here
#if key is pressed, cancel loop and call the manual search function

done