LED flash

#!/usr/bin/env bash

user=my_username
pass=my_password
dir=/Hitachi/Downloads/Temp/


trans="transmission-remote 0.0.0.0:9092 -n $user:$pass -l"


pid_file="/var/run/process.pid"


if [ -f $pid_file ]; then
  exit
else
  echo $$ > $pid_file
fi


flash_red () {

   echo 0 > /sys/class/leds/dart\:white\:power/brightness
while true
 do
   echo 1 > /sys/class/leds/dart\:red\:power/brightness
   sleep 0.5
   echo 0 > /sys/class/leds/dart\:red\:power/brightness
   sleep 0.5
done
}

flash_red &

while
 [ "$($trans | awk '! /awk/ && /n[/]a/ {print $2}')" == "n/a" ] \
 || [[ $($trans | awk '! /awk/ && /%/ {print substr($2, 1, length($2)-1)}' | sort -n | head -n 1) -lt 100 ]] \
 || find $dir -mindepth 1 -maxdepth 1 | read
do
 sleep 10
done

 kill $!
 echo 0 > /sys/class/leds/dart\:red\:power/brightness
 echo 1 > /sys/class/leds/dart\:white\:power/brightness
 rm $pid_file

exit